Datasheet ADP5588 Datasheet (ANALOG DEVICES)

QWERTY Keypad Controller

ADP5588

C8C9C8

C9

18

17

19

21

23

22

20

24

CONTROL

REGISTERS

CONTROL

INTERFACE

REF

VOLTAGE

REF

VOLTAGE

R7R6R5R4R3R2R1R0C0C1C2C3C4C5C6

C7

C9

C8

GND V

CC

SCL SDA

RST

INT

3 4 5 6 7 8 9 10 11 12 13 14 15 161 2

07673-001

ADP5588

Rev. C

Trademarks and registered trademarks are the property of their respective owners.

Data Sheet

FEATURES

18-GPIO port expander or 10 × 8 keypad matrix GPIOs configurable to GPIs, GPOs, and keypad rows or

columns

Dual light sensor inputs (C8 and C9)

2

I

C interface

2

I

C register read autoincrement

1.8 V to 3.0 V operation Keypad lock capability Open-drain interrupt output Key press and key release interrupts GPI interrupt with level programmability Programmable pull-ups Key event counter with overflow interrupt 50 μs debounce on the reset line and GPIs 1 μA typical idle current, 55 μA typical polling current drain

for one key press

Small 4 mm × 4 mm LFCSP package

Mobile I/O Expander and

FUNCTIONAL BLOCK DIAGRAM

Figure 1.

APPLICATIONS

Keypad and I/O expander designed for QWERTY type phones

that require a large keypad matrix

GENERAL DESCRIPTION

The ADP5588 is an I/O port expander and keypad matrix designed for QWERTY type phones that require a large keypad matrix and expanded I/O lines. I/O expander ICs are used in mobile platforms as a solution to the limited number of GPIOs available in the main processor.

In its small 4 mm × 4 mm package, the ADP5588 contains enough power to handle all key scanning and decoding and flag the processor of key presses and releases via the I and interrupt. It frees the main microprocessor from having to monitor the keypad, thereby minimizing current drain and increasing processor bandwidth. It is also equipped with a buffer/FIFO and key event counter to handle and keep track of up to 10 unprocessed key or GPI events with overflow wrap and interrupt capability.

The ADP5588 has a keylock capability with an option to trigger or not trigger an interrupt at key presses and releases. All communication to the main processor is done using one interrupt line and two I configured to have a keypad matrix of up to 8 rows × 10 columns (a maximum of 80 keys).

Information furnishe d by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices.

2

C-compatible interface lines. The ADP5588 can be

2

C® interface

When used for smaller keypad matrices, unused row and column pins can be reconfigured to act as general-purpose inputs, outputs, or light sensor inputs. R0, R1, R2, R3, R4, R5, R6, and R7 denote the row pins of the matrix, while C0, C1, C2, C3, C4, C5, C6, C7, C8, and C9 denote the column pins. At power-up, all rows and columns default as GPIs and must be programmed to function as part of the keypad matrix, GPOs, or light sensor inputs. In addition to keypad and GPIO functionalities, C8 and C9 can also be configured as light sensor inputs.

When configured as keypad lines, the function of the C8 and C9 lines is straightforward: the control interface disconnects these lines from the comparator inputs, disables the light sensor comparator, and connects them to the keypad columns of the keypad matrix. When used as light sensor comparator inputs, the control interface disconnects these pins from the keypad, enables the comparators, and connects these lines to the comparator inputs. Two external capacitors (0.1 μF) are required when these pins are configured as light sensor inputs. When used as GPIOs, these pins are removed from the keypad and the light sensor interface, and the light sensor comparators are disabled, along with the logic for the sensors.

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www.analog.com

ADP5588 Data Sheet

REVISION HISTORY

2/12—Rev. B to Rev. C

Changes to Table 12 .......................................................................... 8

Changes to Table 27 ........................................................................ 18

4/09—Rev. A to Rev. B

Changes to Title ................................................................................ 1

Changes to Ordering Guide .......................................................... 26

11/08—Rev. Sp0 to Rev. A

Keypad Operation .........................................................................7

General-Purpose Inputs and Outputs ........................................9

I2C Programming and Digital Control ........................................ 14

Registers ....................................................................................... 15

Register Descriptions ................................................................. 16

Comparator Register Descriptions .......................................... 21

Applications Information .............................................................. 24

Applications Overview .............................................................. 24

Keypad Current .......................................................................... 24

Backlight Control Application .................................................. 24

Outline Dimensions ....................................................................... 26

Ordering Guide .......................................................................... 26

Rev. C | Page 2 of 28

Data Sheet ADP5588

SPECIFICATIONS

TA = TJ = −40°C to +85°C, unless otherwise noted.

DC ELECTRICAL CHARACTERISTICS

Table 1. General DC Electrical Characteristics

Parameter Symbol Conditions Min Typ Max Unit

SUPPLY VOLTAGE

VCC Input Voltage Range VCC 1.7 3.0 V Photosensor Voltage V Supply Current1 I

PHOTOSENSOR

CC

With One Key Press ICC V With One Key Press ICC V With GPI Low (Pull-Up Enabled)2 I

CC

With GPI Low (Pull-Up Disabled) ICC V With One GPO Active3 I

CC

AMBIENT LIGHT SENSOR (CMP_IN1, CMP_IN2)

Maximum Sensor Range I Sensor Supply Current (One Comparator Enabled,

0 Minimum Input Current)

Sensor Current (One Comparator Enabled,

Maximum Input Current)

Sensor Current (Both Comparators Enabled,

Minimum Input Current)

Sensor Current (Both Comparators Enabled,

Maximum Input Current)

4

SENSOR

I

CC

I

CC

I

CC

I

CC

OSCILLATOR CURRENT

Oscillator Current (Enabled) ICC V

1

Operating current measured with I/Os defaulting as GPIs with all pull-ups enabled and all inputs open.

2

With one GPI low.

3

Load = 100 k.Ω

4

Photosensor maximum voltage = VCC + 0.2.

Table 2. I/O DC Electrical Characteristics

Parameter Symbol Conditions Min Typ Max Unit

INPUT LOGIC LEVELS (SCL, SDA, RST, C0 to C9, R0 to R7)1

Logic Low Input Voltage VIL 1.7 V ≤ VIO ≤ 3.0 V 0.2 x VCC V Logic High Input Voltage VIH 1.7 V ≤ VIO ≤ 3.0 V 0.65 x VCC V Schmitt Trigger Hysteresis V Input Leakage Current V

HYST

I-LEAKAGE

OUTPUT LOGIC LEVELS (C0 to C9, R0 to R7)

Logic Low Output Voltage VOL I Output High Voltage VOH I

OUTPUT LOGIC LEVELS (INT, SDA)

Output Low Voltage VOL I

Output High Voltage VOH 1.7 V ≤ VCC ≤ 3.0 V 0.95 × VCC V Logic High Leakage Current V

PULL-UP RESISTANCE FOR GPIOs (C0 to C9, R0 to R7)2 R

1

Power-up default current. All I/Os default as GPIs and are open; C8 and C9 default as GPIs; I2C is idle.

2

GPIO internal pull-ups are designed to 100 kΩ.

O-LEAKAGE

PULL-UP

VCC + 0.2

V

= 1.8 V to 3.0 V, TA = −40°C to +85°C 1 10 A

CC

= 1.8 V, TA = −40°C to +85°C 55 90 A

CC

= 3.0 V, TA = −40°C to +85°C 100 200 A

CC

= 1.8 V to 3.0 V, TA = −40°C to +85°C 20 50 A

CC

= 1.8 V to 3.0 V, TA = −40°C to +85°C 2 10 A

CC

= 1.8 V, TA = −40°C to +85°C 50 A

CC

= 1.8 V to 3.0 V, TA = 25°C 0.85 1.0 1.15 mA

CC

= 1.8 V to 3.0 V 100 150 A

CC

= 1.8 V to 3.0 V 160 200 A

CC

= 1.8 V to 3.0 V 130 180 A

CC

= 1.8 V to 3.0 V 240 400 A

CC

= 1.8 V to 3.0 V 40 A

CC

0.10 V

1.7 V ≤ VIO ≤ 3.0 V −1 1 µA

= 1 mA 0.40 V

SINK

= 1 mA VCC − 0.3 V V

SOURCE

= 3 mA

SINK

1.7 V ≤ V

≤ 3.0 V

CC

0.40 V

1.7 V ≤ VCC ≤ 3.0 V 0.1 1 µA

100 kΩ

Rev. C | Page 3 of 28

ADP5588 Data Sheet

p

Table 3. Comparator Input Capacitor

Parameter Symbol Min Typ Max Unit

Comparator Input Capacitor Value C

Table 4. Capacitance Loading1

Parameter Symbol Min Typ Max Unit

I/O Input Capacitance C I/O Output Loading Capacitance C Capacitive Load for Each Bus Line C

1

Guaranteed by design.

2

CB = total capacitance of one bus line in picofarads.

Table 5. AC Characteristics1

Parameter Symbol Min Typ Max Unit

Delay from Reset Deassertion to I2C Access R Keypad Unlock Timer T Keypad Interrupt Mask Timer T Debounce TD 50 μs Filter Time T

1

Guaranteed by design.

2

Table 6. I

C AC Electrical Characteristics1

Parameter Symbol Min Typ Max Unit

SCL Clock Frequency f SCL High Time t SCL Low Time t Data Setup Time tSU, Data Hold Time tHD, Setup Time for Repeated Start tSU, Hold Time for Start/Repeated Start tHD, Bus Free Time for Stop and Start t Setup Time for Stop Condition tSU, Rise Time for SCL and SDA2 t Fall Time for SCL and SDA2 t Pulse Width of Suppressed Spike tSP 0 50 μs

1

Guaranteed by design.

2

tR and tF are measured between 0.3 × VCC and 0.7 × VCC.

0.1 μF

COMP

IN

OUT

2

B

60 μs

STD

7 sec

KUT

31 sec

KIMT

0.070 12 sec

TTR

400 kHz

SCL

0.6 μs

HIGH

1.3 μs

LOW

100 ns

DAT

0 0.9 μs

DAT

0.6 μs

STA

0.6 μs

STA

1.3 μs

BUF

0.6 μs

STO

20 + 0.1 CB 300 ns

R

20 + 0.1 CB 300 ns

F

1 10

50 400

F F F

SDA

t

LOW

SCL

S

S = START CONDITION Sr = REPEATED START CONDITION P = STOP CO NDITION

t

R

t

HD, DAT

t

SU, DAT

t

HIGH

Figure 2. I

t

F

t

F

t

SU, STA

2

C Interface Timing Diagram

Sr P S

t

HD, STA

t

SP

t

SU, STO

BUF

t

R

07673-002

Rev. C | Page 4 of 28

Data Sheet ADP5588

ABSOLUTE MAXIMUM RATINGS

Table 7.

Parameter Rating

VCC −3 V to +4.0 V R0 to R7, C0 to C9 −3 V to VCC + 0.3 V SCL −3 V to VCC+ 0.3 V SDA −3 V to VCC + 0.3 V

−3 V to VCC + 0.3 V

RST

−3 V to VCC + 0.3 V

INT GND −0.3 V to +0.3 V Operating Ambient Temperature Range −40°C to +85°C Operating Junction Temperature Range −40°C to +125°C Storage Temperature Range −65°C to +150°C ESD Machine Model ±200 V ESD Human Body Model ±2000 V ESD Charged Device Model ±1000 V Soldering Condition JEDEC J-STD-020

Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

THERMAL RESISTANCE

θJA is specified for the worst-case conditions, that is, a device soldered in a circuit board for surface-mount packages.

Table 8. Thermal Resistance

Package Type θJA θJC Unit

24-Lead LFCSP_VQ 57.8 9.4 °C/W Maximum Power 600 mW

ESD CAUTION

Rev. C | Page 5 of 28

ADP5588 Data Sheet

PIN 1 INDICATOR

NOTES

1. NC = NO CONNECT.

2. EXPOSED PAD MUST BE CONNECTED TO GROUND.

1R7 2R6 3R5 4R4 5R3 6R2

15 C6

16 C7

17 CMP_IN1/C8

18 CMP_IN2/C9

14 C5 13 C4

7 R1

8R0

9C0

11C2

12C3

10C1

21

V

CC

22

SDA

23

SCL

24

INT

20

RST

19

GND

TOP VIEW

(Not to S cale)

ADP5588

07673-003

8

R0

GPIO, Row 0 in the Keypad Matrix.

23

SCL

I2C Clock.

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

Figure 3. Pin Configuration

Table 9. Pin Function Descriptions

Pin No. Mnemonic Description

1 R7 GPIO, Row 7 in the Keypad Matrix. 2 R6 GPIO, Row 6 in the Keypad Matrix. 3 R5 GPIO, Row 5 in the Keypad Matrix. 4 R4 GPIO, Row 4 in the Keypad Matrix. 5 R3 GPIO, Row 3 in the Keypad Matrix. 6 R2 GPIO, Row 2 in the Keypad Matrix. 7 R1 GPIO, Row 1 in the Keypad Matrix.

9 C0 GPIO, Column 0 in the Keypad Matrix. 10 C1 GPIO, Column 1 in the Keypad Matrix. 11 C2 GPIO, Column 2 in the Keypad Matrix. 12 C3 GPIO, Column 3 in the Keypad Matrix. 13 C4 GPIO, Column 4 in the Keypad Matrix. 14 C5 GPIO, Column 5 in the Keypad Matrix. 15 C6 GPIO, Column 6 in the Keypad Matrix. 16 C7 GPIO, Column 7 in the Keypad Matrix. 17 CMP_IN1/C8 GPIO, Column 8 in the Keypad Matrix; Comparator Input for Photosensor 1. 18 CMP_IN2/C9 GPIO, Column 9 in the Keypad Matrix; Comparator Input for Photosensor 2. 19 GND Ground. 20

Hardware Reset (Active Low). This bit resets the device to the power default conditions. The reset pin must be

RST

driven for a minimum of 50 μs to be valid and to prevent falsing due to ESD glitches or noise in the system. If not used,

must be tied high with a pull-up.

RST 21 VCC VCC = 1.7 V to 3.3 V. 22 SDA I2C Serial Data (Open Drain Requires External Pull-up).

24

Processor Interrupt, Active Low, Open Drain. This pin can be pulled up to 2.7 V or 1.8 V for selection flexibility in

INT

the processor GPIO supply group.

EP EPAD Exposed Pad. The exposed pad must be connected to ground.

Rev. C | Page 6 of 28

Data Sheet ADP5588

CONTROL

REGISTERS

CONTROL

INTERFACE

REF

VOLTAGE

C9

C8

R7R6R5R4R3R2R1R0C0C1C2C3C4C5C6

C7

C9

C8

A0A1A2A3A4A5A6A7 B0B1B2B3B4B5B6B7 C0C1C2C3C4C5C6C7 D0D1D2D3D4D5D6D7 E0E1E2E3E4E5E6E7 F0F1F2F3F4F5F6F7 G0G1G2G3G4G5G6G7 H0H1H2H3H4H5H6H7

I0I1I2I3I4I5I6I7

J0J1J2J3J4J5J6J7

SCL

SDA

RST

INT

V

CC

GND

V

CC

SCL SDA

19

21

23

22

18

17

20

24

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16

REF

VOLTAGE

0.1µF

V

CC

07673-009

ADP5588

RST

INT

R2

21

22

23

24

25

26

27

28

29

30

R4

R5

51

52

53

54

55

56

57

58

59

60

THEORY OF OPERATION

Figure 4. Typical Operating Circuit

The ADP5588 is a GPIO expander that can be configured either as an 18-I/O port expander or as a 10 column × 8 row keypad matrix (80 keys maximum). It is ideal for cellular phone designs and other portable devices that require a large extended keypad

Table 10. Key Event Number Assignment Table

Row C0 C1 C2 C3 C4 C5 C6 C7 C8 C9

1 2 4 4 5 6 7 8 9 10

R0

11 12 13 14 15 16 17 18 19 20

R1

and/or expanded I/Os (see the Applications Information section for various configurations). When smaller size keypads are required, unused GPIOs in the keypad matrix can be used as

31 32 33 34 35 36 37 38 39 40

R3

41 42 43 44 45 46 47 48 49 50

I/Os (GPOs and GPIs). Two of the columns (C8 and C9) can also be configured as comparator inputs for single or dual light sensors. All GPIOs (rows and columns) default as GPIs at powerup with pull-ups and debounce enabled.

KEYPAD OPERATION

Any number of rows and columns, up to 10 columns × 8 rows, can be configured to be part of the keypad matrix. The rows and columns that make up the keypad matrix must be configured by setting the corresponding bits in Register 0x1D through Register 0x1F. Keys on the keypad matrix appear on the key event table with a decimal value of 1 (0x01 hexidecimal or 0000001 binary) and run through 80 decimals (0x50 hexidecimal or 1010000 binary). See Ta b l e 10 for key event number assignments. The keypad, in idle mode, is configured with columns being driven low and rows as inputs high with pull-ups.

Rev. C | Page 7 of 28

61 62 63 64 65 66 67 68 69 70

R6

71 72 73 74 75 76 77 78 79 80

R7

When one key press or multiple key presses (short between coumn and row) occur, the internal state machine checks the row pins to determine which one is driven low and then triggers an interrupt. The state machine then starts a key scan cycle to determine which keys are pressed. After a key has been pressed for 25 ms, the state machine sets the appropriate key(s) in the key event status register with the key-pressed bits set (the MSB in the key event register) in the order detected. If the KE_IEN field in Register 0x01 is set, the state machine then sets the KE_INT field in Register 0x01 and generates an interrupt to the host processor.

ADP5588 Data Sheet

KEYPAD SCAN AND DECODE

D0_PULL

J7

I7

H7

G7

F7

E7

D7

C7

B7

A7

J6

I6

H6

G6

F6

E6

D6

C6

B6

A6

J5

I5

H5

G5

F5

E5

D5

C5

B5

A5

J4

I4

H4

G4

F4

E4

D4

C4

B4

A4

J3

I3

H3

G3

F3

E3

D3

C3

B3

A3

J2

I2

H2

G2

F2

E2

D2

C2

B2

A2

J1

I1

H1

G1

F1

E1

D1

C1

B1

A1

J0

I0

H0

G0

F0

E0

D0

C0

B0

A0

R7 R6 R5 R4 R3 R2 R1

R0

C0 C1 C2 C3 C4 C5 C6 C7 C9C8

10 × 8 KEYPAD MATRI X

V

CC

D1_PULL

D2_PULL

D3_PULL

D4_PULL

D5_PULL

D6_PULL

D7_PULL

07673-010

E4

Released

9

7 C 0 0000001

Key A0 released

To prevent glitches or narrow press times registering as valid key presses, the key scanner requires the key to be pressed for two scan cycles. The key scanner has a sampling period of 25 ms, so the key must be pressed and held for at least 25 ms to register as pressed. If the key is continuously pressed, the key scanner continues to sample every 25 ms. If a key that was pressed is released for 25 ms or greater, the state machine sets the appropriate keys in the key event status register with the key pressed bits cleared in the order detected. Because the release of a key is not necessarily in sync with the key scan sampling period, it may take between 25 ms and 50 ms for a key to register as released. After the key is registered as released, the key scanner goes back to idle mode. Figure 5 shows the row and column pins connected to a typical 10 × 8, 80-switch keypad matrix.

The first read of any of the FIFO registers displays the first event that happened and its status. Subsequent reads of the same register replace the register data with the next event that happens. If tracking of all the events is important, it is best to used a single register per event. After all the events in the FIFO are read, reading of any of the event registers yields a zero value.

Table 11 and Tabl e 12 show the event sequences as they are logged in and read from the FIFO. The 10 FIFO registers are labeled A through J, and keys are labeled A0 through J7.

Table 11. Example of Event Sequence

Key Pressed/Released Status Key Event Counter

A0 Pressed 1 B1 Pressed 2 A0 Released 3 C2 Pressed 4 B1 Released 5 D3 Pressed 6 C2 Released 7 E4 Pressed 8

D3 Released 10

Key Event Tracking

The 10-key event registers are set to act as a FIFO, meaning that reading any of the 10-key event registers yields the key events in the order they were pressed and released.

Tracking of key events is done with the help of the key event counter (the KEC field in Register 0x03) and the FIFO/key event registers (Register 0x04 through Register 0x0D). The KEC count increases as keys are pressed and released; up to 10 events can be logged in the count e r. The FIFO/key event registers, on the other hand, display the key events and their status (pressed or released) as they are read out of the FIFO. The FIFO registers are made of eight bits, with the MSB dedicated as the status bit (1 indicates a press and 0 indicates a release); the remaining seven bits are used to display binary representation of the keys that are pressed or released.

Figure 5. Keypad Decode Configuration

Rev. C | Page 8 of 28

Table 12. Interpretation of FIFO Event Reading

Key Event Register Interpretation

Key Event Counter

Key Event Register Read

Key Event Register Content (Binary)

1

10 N/A N/A N/A 9 D 1 0000001 Key A0 pressed 8 E 1 0001100 Key B1 pressed

6 F 1 0010111 Key C2 pressed 5 G 0 0001100 Key B1 released 4 A 1 0100010 Key D3 pressed 3 B 0 0010111 Key C2 released 2 H 1 0101101 Key E4 pressed 1 J 0 0101101 Key E4 released 0 I 0 0100010 Key D3 released

1

The first number indicates a key press or key release in Bit 7 of the key event

register: 1 = key press; 0 = key release.

Key Event Overflow

The ADP5588 is equipped with an overflow feature to handle key events beyond the FIFO capacity. When all events are filled, any additional events set the OVR_FLOW_INT bit in Register 0x02; if the OVR_FLOW_IEN bit in Register 0x01 is set, the host processor is also interrupted when overflow occurs. When the FIFO is not full, new events are added as the last events.

The OVR_FLOW_M bit in Register 0x01 sets the mode of operation during overflows. Clearing the OVR_FLOW_M bit causes new incoming events to be discarded, and setting this bit rolls over and overwrites old data with new data starting at the first event.

Data Sheet ADP5588

KP_MODE

KEC

REG. 0x1D

THROUGH 0x1F

REG. 0x03

READ KE(s) TO CLEAR

INT DRIVE

KE_INT

REG. 0x02

WRITE 1 TO CLEAR

KE_IEN

REG. 0x01

07673-011

AND

DEBOUNCE

GPIOx

Dx_DIR

Dx_OUT

Dx_IN

Dx_IN_DBNC

Dx_PULL

V

CC

V

CC

07673-012

Autoincrement

The ADP5588 features automatic increment during I2C read access. This allows the user to increment the address pointer without having to send a read command for subsequent addresses. This minimizes processor intervention and, therefore, saves processor bandwidth and current drain. Bit 7 of Register 0x01 must be set to initiate autoincrement (see Figure 16 for the full write and read sequence).

Key Event Interrupt

On a key event (KE) interrupt, the processor reads the interrupt register to determine the cause of the interrupt. If the KE_INT bit in Register 0x02 is the cause of the interrupt, the state machine sets the KE_INT bit and reads the key event count from the KEC[3:0] field in Register 0x03 to determine the number of events. It then reads the INT_STAT register (Register 0x02) to make sure that no new events have come in. After all the events are read, the KEC field is decremented to zero (KEC =0) and the KE_INT bit can be cleared by writing a 1 to it. Both key presses and key releases are capable of generating key event interrupts. The KE_INT bit cannot be cleared, and the

INT

cannot be deasserted, until the FIFO is cleared of all events.

display the unlock message. The host then reads the lock status register to see if the keypad is unlocked. After the first key event interrupt, the state machine does not interrupt the processor again unless the correct sequence is keyed. The state machine resets if the correct sequences are not keyed before the keypad lock interrupt mask timer expires.

The state of the keypad lock interrupt mask bit (Register 0x01, Bit 2) in the configuration register determines whether the interrupt pin is asserted when the keylock interrupt status bit (Register 0x02, Bit 2) is set. Setting the keylock interrupt mask bit causes the

INT

pin to be asserted when the keylock interrupt status bit is set in Register 0x02; clearing that bit masks the interrupt, causing the interrupt pin not to respond to the keylock interrupt status bit. The mask interrupt timer should be set for the time that it takes for the LCD to dim or turn off so that, if a key is pressed, the backlight is set to bright mode again or reset to turn on the LCD.

When the unlock mask interrupt timer equals 0, only the correct unlock sequence can generate an interrupt. Disabling the unlock mask interrupt timer allows the processor to remain undisturbed for situations in which the user has the phone in a pocket or purse and the keys are constantly pressed. The flow chart in Figure 6 shows the interaction of the interrupt mask timer and interrupt generation.

Keypad Lock/Unlock Feature

The ADP5588 has a locking feature that allows the user to lock the keypad or GPIs (configured to be part of the event table). Once enabled, the keypad lock can prevent generation of key event interrupts and key events to be recorded in the key event table. This feature comprises the Unlock Key 1 and Unlock Key 2 registers (Register 0x0F and Register 0x10), the keypad lock interrupt mask, the keypad unlock timers (Register 0x0E), and the LCK1 and LCK2 bits, and the keylock enable bit (Register 0x03).

The unlock keys can be programmed with any value of the keys in the keypad matrix or any GPI values that are part of the key event table. When the keypad lock interrupt mask timer is enabled, the user must press two specific keys before a keylock interrupt is generated or keypad events are recorded. After the keypad is locked (set Bit 6, Register 0x03 to enable the lock), the first time that the user presses any key, a key event interrupt is generated. No additional interrupt is generated unless both unlock key sequences are correct; then a keylock interrupt is generated.

If the correct unlock keys are not pressed before the mask timer expires, the state machine starts over. The first key event interrupt is generated to allow the software to see that the user has pressed a key so that the host can turn on the LCD and

Figure 6. Key Event Interrupt Generation

GENERAL-PURPOSE INPUTS AND OUTPUTS

The ADP5588 supports up to 18 programmable GPIOs that can

Rev. C | Page 9 of 28

be configured to address a variety of uses. Figure 7 shows the makeup of a typical GPIO block where GPIOx represents any of the 18 I/O lines.

General Purpose Inputs (GPI)

The ADP5588 allows the user to configure all or some of its GPIOs into GPIs (general-purpose inputs). After the GPIOs are configured as GPIs, the user can opt to also turn on pull-up resistors and interrupt generation capability, thus reducing the amount of software monitoring and processor interaction and saving p ower.

The programmed level of the GPI interrupt determines the active level of the GPI pin. For example, if a GPI interrupt level

Figure 7. Typical GPIO Block

ADP5588 Data Sheet

Dx_IN

Dx_IN_IEN

REG. 0x23

THROUGH 0x25

Dx_IN_ISTAT

REG. 0x11

THROUGH 0x13

READ TWICE

TO CLEAR

GPI_INT

REG. 0x02

WRITE 1

TO CLEAR

REG. 0x01

INT DRIVE

INTERRUPT

CONDITION

DECODE

Dx_ILVL

REG. 0x26

THROUGH 0x28

07673-013

AND

COMPARATO R 1 INTERRUPT

KEY EVENT INTERRUPT

KEYLOCK I NTERRUPT

OVERFLOW INTERRUPT

COMPARATO R 2 INTERRUPT

GPIO INTERRUPT

INT

OR

INTERRUPT CONFIGURATION

OVR_FLOW_

IEN

K_LCK_IM GPI_IEN KE_IEN

GPIEM_

CFG

KEYPAD LOCK INTERRUPT MAS K TIMER

K_LCK_EN

INT

LOGIC

V

CC

07673-014

is programmed as high, a high on that pin is considered active and meets the interrupt requirement. If the interrupt is programmed as low, a low on that pin is considered active and meets the interrupt requirement.

GPI data and interrupt status are reflected in the GPIO interrupt and data status registers (Register 0x11 through Register 0x16). Caution must be taken during software implementation because an interrupt may be set immediately after register settings. To prevent this, correct logic levels must be present at the GPIs, and the GPIO interrupt level must be set before GPIO interrupt enable or GPI event FIFO enable registers are set. Figure 8 shows the interrupt generation scheme, where Dx represents any one of the 18 GPIOs.

Figure 8. GPIO Interrupt Generation

GPI Events

A column or row configured as a GPI can be programmed to be part of the key event table and therefore also capable of generating a key event interrupt. A key event interrupt caused by a GPI follows the same process flow as a key event interrupt caused by a key press. GPIs configured as part of the key event table allow single key switches and other GPI interrupts to be monitored. As part of the event table, GPIs are represented by the decimal value 97 (0x61 or 1100001) through the decimal value 114 (0x72 or 1110010). See Ta b l e 13 and Table 14 for GPI event number assignments for rows and columns.

Table 13. GPI Event Number Assignments for Rows

R0 R1 R2 R3 R4 R5 R6 R7

97 98 99 100 101 102 103 104

Table 14. GPI Event Number Assignments for Columns

C0 C1 C2 C3 C4 C5 C6 C7 C8 C9

105 106 107 108 109 110 111 112 113 114

For a GPI that is set as active high, and is enabled in the key event table, the state machine adds an event to the event count and event table whenever that GPI goes high. If the GPI is set to active low, a transition from high to low is considered a press and is also added to the event count and event table. After the interrupt state is met, the state machine internally sets an interrupt for the opposite state programmed in the register to prevent polling for the released state, thereby saving current. After the released state is achieved, it is added to the event table. The press and release are still indicated by Bit 7 in the event register (Register 0x04 through Register 0x0D). The GPI events can also be used as unlocked sequences.

When the GPI_EM_REGx bit in Register 0x20 through Register 0x22 is set, GPI events are not tracked when the keypad is locked. The GPIEM_CFG bit (Register 0x01, Bit 6) must be cleared for the GPI events to be tracked in the event counter and event table when the keypad is locked.

50 Microsecond Interrupt Configuration

The ADP5588 gives the user the flexibility of deasserting the interrupt for 50 μs while there is a pending event. When the INT_CFG bit in Register 0x01 is set, any attempt to clear the interrupt bit while the interrupt pin is already asserted results in a 50 μs deassertion. When the INT_CFG bit is cleared, processor interrupt remains asserted if the host tries to clear the interrupt. This feature is particularly useful for software development and edge triggering applications.

INT

Figure 9.

Rev. C | Page 10 of 28

Pin Drive

Data Sheet ADP5588

START

MASK TIMER = 0

KEY PRESS

DETECTED

NO

YES

NO

YES

NO

YES

NO

YES

NO

YES

NO

GENERATE

KE INTERRUPT

START MASK TIMER

MASK TIMER

EXPIRES

MASK TIMER

EXPIRES

GENERATE

KEYLOCK I NTERRUPT

FIRST UNLOCK

KEY DETECTED

SECOND UNLO CK

KEY DETECTED

START UNLOCK1 TO UNLOCK2

UNLOCK1 TO

UNLOCK2

TIMER EXPIRES

KEY PRESS

DETECTED

START UNLOCK1 TO UNLOCK2

FIRST UNLOCK

KEY DETECTED

GENERATE

KEYLOCK I NTERRUPT

SECOND UNLO CK

KEY DETECTED

UNLOCK1 TO

UNLOCK2

TIMER EXPIRES

NO

07673-015

Debouncing

The ADP5588 has a 50 μs debounce time for GPIOs configured as GPIs and rows in keypad scanning mode. The reset line always has a 50 μs debounce time.

General Purpose Outputs (GPOs)

GPIOs as GPOs. These GPOs can be used as extra enables for the host processor or simply as trigger outputs. When configured

The ADP5588 allows the user to configure all or some of its

as an output (GPO), a digital buffer drives the pin to 0 V for a 0 and to V the corresponding bits in Register 0x1D through Register 0x1F are set for GPIO mode; then use Register 0x23 through Register 0x25

for a 1. To se t any GPIO as a GPO, make sure that

CC

Figure 10. Keypad Lock Interrupt Mask T imer Flowchart

to set the corresponding bits for GPO mode.

Rev. C | Page 11 of 28

Power-On Reset

For built-in power-up initialization for applications lacking a power-on reset signal, a reset pin,

RST

, allows the user to reset the registers to default values in the event of a brownout or other reset conditions.

Ambient Light Sensing

The ADP5588 has built in light sensor comparator inputs to detect ambient light conditions. An ADC samples the output of external photosensors connected to the comparator inputs, and the result is fed into programmable trip comparators. The ADC has an input range of 0 μA to 1000 μA (typical). The device can handle up to two photosensors (use Register 0x30 through Register 0x3A to configure the photosensor inputs).

ADP5588 Data Sheet

BRIGHTNESS

L3 L2

DARK OFFICE OUTDOOR

0 LUX

1 kLUX

0µA

1000µA

L2 = 1

L3 = 1

L2 = 1 L3 = 0

L2 = 0 L3 = 0

07673-016

L3_TRIP

L2_TRIP

L3_HYST

L2_HYST

1 10 100 1000

ADC RANGE (µA)

07673-017

L2_TRIPL2_HYST

FILTER

SETTING

L2_EN

L2_OUT

L3_OUT

COMP INPUT

ADC

PHOTO-

SENSOR

L3_EN

V

CC

L2_CMP

L3_CMP

L3_TRIPL3_HYST

07673-018

Light Sensor Inputs

Each light sensor input has two built-in comparators (the L2 comparator and the L3 comparator) with two programmable trip points, L2 and L3. The trip points are used to select among three operation modes based on ambient lighting conditions: outdoor, office, and dark modes.

Figure 11. Light Sensor Comparator Modes and Trip Points

L2 Comparator

The L2 comparator is used to detect when the photosensor output drops below the programmable L2_TRIP point. When this event occurs, the L2_OUT status signal is set. L2_CMPR contains programmable hysteresis, meaning that the photosensor output must rise above L2_TRIP + L2_HYS before L2_OUT is cleared.

L2_CMPR is enabled via the L2_EN bit (Bit 0, Register 0x31 for Sensor 1 and Bit 0, Register 0x32 for Sensor 2). The L2_TRIP and L2_HYS values of L2_CMPR can be set between 0 μA and 1000 μA in steps of 4 μA.

L3 Comparator

The L3 comparator is used to detect when the photosensor output drops below the programmable L3_TRIP point. When this event occurs, the L3_OUT status signal is set. L3_CMPR contains programmable hysteresis, meaning that the photosensor output must rise above L3_TRIP + L3_HYS before L3_OUT is cleared. L3_CMPR is enabled via the L3_EN bit. The L3_TRIP and L3_HYS values of L3_CMPR can be set between 0 μA and 127.5 μA in steps of 0.5 μA.

The L2_CMPR and L3_CMPR comparators can be enabled independently of each other, and the ADC and comparator(s) run continuously when L2_EN and/or L3_EN is set.

Photosensor Operation

The comparator inputs remain idle until enabled, at which point they detect lighting conditions from the photosensor output. Depending on lighting conditions, and where the L2 and L3 trip points are set in the comparator level trip registers (Register 0x33 through Register 0x3A), the comparators set a value of 1 or 0 to L2_OUT and L3_OUT. The values of L2 and L3 determine what mode or setting adjustment is required for a particular lighting condition. Figure 11, Figure 12, and Tabl e 15 summarize the mode settings and logical values of L2 and L3.

Table 15. L2_OUT and L3_OUT Comparator Mode Combination

L3 L2 Mode

0 0 Outdoor 0 1 Office 1 1 Dark

It is also possible to use the light sensor comparators in singleshot mode. A single-shot measurement is done when the FORCE_RD bit in Register 0x31 is set. After the single-shot measurement is completed, the internal state machine clears the FORCE_RD bit. It takes 80 ms for a complete conversion. To reduce the potential for flickering, the sensors can be programmed for a number of sequential readings. The filter settings in Register 0x31 and Register 0x32 determine the number of sequential readings needed by the user; these settings range from 80 ms to 10.24 sec.

Figure 12. Comparator Ranges

Rev. C | Page 12 of 28

Figure 13. Light Sensor and Trip Points Block Diagram

Data Sheet ADP5588

Comparator Interrupt

The ADP5588 allows the user to trigger an interrupt based on the light sensor comparator inputs. Changes in lighting condition that cause the settings of L2 and L3 to jump from one mode to another (dark, office, outdoor) set the comparator interrupt bits

Table 16. Device Configuration

Keypad GPIO Photosensor Inputs

Matrix Active Pins Number of Keys Available GPIO Number of GPIOs

10 × 8 C0 to C9, R0 to R7 80 0 0 None 0 8 × 8 C0 to C7, R0 to R7 64 0 0 C8, C9 2

C8 1 C9 1 C9 1 C8 1

8 × 7 C0 to C7, R0 to R6 56 R7 1 C8, C9 2

C8, R7 2 C9 1 R7, C8, C9 3 None 0

8 × 6 C0 to C7, R0 to R5 48 R6, R7 2 C8, C9 2

R6, R7, C8 3 C9 1 R6, R7, C8, C9 4 None 0

8 × 5 C0 to C7, R0 to R4 40 R5, R7 3 C8, C9 2

R5 to R7, C8 4 C9 1 R5 to R7, C8 to C9 5 None 0

7 × 7 C0 to C6, R0 to R6 49 R7, C7 2 C8, C9 2

R7, C7 to C8 3 C9 1 R7, C7 to C9 4 None 0

7 × 6 C0 to C6, R0 to R5 42 R6 to R7, C7 3 C8, C9 2

R6 to R7, C7 to C8 4 C9 1 R6 to R7, C7 to C9 5 None 0

7 × 5 C0 to C6, R0 to R4 35 R5 to R7, C7 4 C8, C9 2

R5 to R7, C7 to C8 5 C9 1 R5 to R7, C7 to C9 6 None 0

6 × 6 C0 to C5, R0 to R5 36 R6 to R7, C6 to C7 4 C8, C9 2

R6 to R7, C6 to C8 5 C9 1 R6 to R7, C6 to C9 6 None 0

6 × 5 C0 to C5, R0 to R4 30 R5 to R7, C6 to C7 5 C8, C9 2

R5 to R7, C6 to C8 6 C9 1

R5 to R7, C6 to C9 7 None 0 6 × 4 C0 to C5, R0 to R3 24 R4 to R7, C6 to C7 6 C8, C9 2 R4 to R7, C6 to C8 7 C9 1 R4 to R7, C6 to C9 8 None 0 … … … … … … … 0 × 0 None 0 R0 to R7, C0 to C9 18 None 0

in Register 0x02. If the comparator interrupt enable bits are set, the interrupt pin is asserted every time the comparator interrupt bits are set. The comparator interrupt flag can be cleared only by writing a 1 to it.

Photosensor Input Pin(s)

Number of Photosensor Inputs

Rev. C | Page 13 of 28

ADP5588 Data Sheet

SUBADDRESSCHIP ADDRESS

ST 0 1 1 0 0 0 0 0 0 0 SP

0 = WRITE

ADP5588 ACK

ADP5588 RECEIVES DATA

ADP5588 ACK

07673-019

0

SUBADDRESSCHIP ADDRESS CHIP ADDRESS

ST 0 1 1 0 0 0

0 0 0 0 0 0 0 0 1 1 0 ST 0 1 1 0 0 0 0 0 1 SP

1 = READ

ADP5588 NO ACK

ADP5588 SENDS DATA

ADP5588 ACK

07673-020

0 = WRITE

0 1

READ START ADDRCHIP ADDRESS CHIP ADDRESS

ST 0 1 1 0 1 0 0 0 0 0 0 0 0 0 1 1 0 ST 0 1 1 0 1 0 0 0 0

1 = READ

ADP5588 ACK

ADP5588 SENDS DATA 1

ADP5588 ACK

07673-021

0 = WRIT E

0 1

ADP5588 NO ACK

1

ADP5588 SENDS DATA N

...

ST

STOP

START

I2C PROGRAMMING AND DIGITAL CONTROL

The ADP5588 provides full software programmability to facilitate its adoption in various product architectures. All register programming is done via the I

2

C bus at Address 0x69

(01101001) for a read and Address 0x68 (01101000) for a write.

All communication to the ADP5588 is done via its I

2

C-compatible serial interface. Figure 14 shows a typical write sequence for programming an internal register. The cycle begins with a start condition followed by the chip write address (0x68). The ADP5588 acknowledges the chip write address byte by pulling the data line low. The address of the register to which data is to be written is sent next. The ADP5588 acknowledges the register address byte by pulling the data line low. The data byte to be written is sent next. The ADP5588 acknowledges the data byte by pulling the data line low. A stop condition completes the sequence.

Figure 15 shows a typical read sequence for reading back an internal register. The cycle begins with a start condition followed by the chip write address (0x68). The ADP5588 acknowledges the chip write address byte by pulling the data line low. The address of the register from which data is to be read is sent next. The ADP5588 acknowledges the register address byte by pulling the data line low. The cycle continues with a repeat start followed by the chip read address (0x69). The ADP5588 acknowledges the chip read address byte by pulling the data line low. The ADP5588 places the contents of the previously addressed register on the bus for readback. There is no acknowledge following the readback data byte, and the cycle is completed with a stop condition.

Figure 14. I

2

C Write Sequence

Figure 15. I

2

C Read and Write Sequences

Figure 16. I

2

C Read Autoincrement

Rev. C | Page 14 of 28

Data Sheet ADP5588

0x0A

KEY_EVENTG

Key Event Register G

0x1B

GPIO_INT_EN2

GPIO interrupt enable

0x2C

GPIO_PULL1

GPIO pull disable

REGISTERS

The general behavior of registers is as follows:

• All registers are 0 on reset.

• All registers are read/write unless otherwise specified.

• Unused bits are read as 0.

• Interrupt bits are cleared by writing 1 to the flag; writing 0

or reading the flag has no effect, with the exception of the key press, key release, and GPIO interrupt status registers, which are cleared on a read.

Table 17.

Address Register Name Description

0x00 DEV_ID Device ID 0x01 CFG Configuration Register 1 0x02 INT_STAT Interrupt status register 0x03 KEY_LCK_EC_STAT Keylock and event counter register 0x04 KEY_EVENTA Key Event Register A 0x05 KEY_EVENTB Key Event Register B 0x06 KEY_EVENTC Key Event Register C 0x07 KEY_EVENTD Key Event Register D 0x08 KEY_EVENTE Key Event Register E 0x09 KEY_EVENTF Key Event Register F

0x0B KEY_EVENTH Key Event Register H 0x0C KEY_EVENTI Key Event Register I 0x0D KEY_EVENTJ Key Event Register J 0x0E KP_LCK_TMR Keypad Unlock 1 to Keypad Unlock 2 timer 0x0F UNLOCK1 Unlock Key 1 0x10 UNLOCK2 Unlock Key 2 0x11 GPIO_INT_STAT1 GPIO interrupt status 0x12 GPIO_INT_STAT2 GPIO interrupt status 0x13 GPIO_INT_STAT3 GPIO interrupt status 0x14 GP IO_DAT_STAT1 GPIO data status, read twice to clear 0x15 GP IO_DAT_STAT2 GPIO data status, read twice to clear 0x16 GP IO_DAT_STAT3 GPIO data status, read twice to clear 0x17 GPIO_DAT_OUT1 GPIO data out 0x18 GPIO_DAT_OUT2 GPIO data out 0x19 GPIO_DAT_OUT3 GPIO data out 0x1A GPIO_INT_EN1 GPIO interrupt enable

0x1C GPIO_INT_EN3 GPIO interrupt enable 0x1D KP_GPIO1 Keypad or GPIO selection 0x1E KP_GPIO2 Keypad or GPIO selection 0x1F KP_GPIO3 Keypad or GPIO selection 0x20 GPI_EM_REG1 GPI Event Mode 1 0x21 GPI_EM_REG2 GPI Event Mode 2 0x22 GPI_EM_REG3 GPI Event Mode 3 0x23 GPIO_DIR1 GPIO data direction 0x24 GPIO_DIR2 GPIO data direction 0x25 GPIO_DIR3 GPIO data direction 0x26 GPIO_INT_LVL1 GPIO edge/level detect 0x27 GPIO_INT_LVL2 GPIO edge/level detect 0x28 GPIO_INT_LVL3 GPIO edge/level detect 0x29 DEBOUNCE_DIS1 Debounce disable 0x2A DEBOUNCE_DIS2 Debounce disable 0x2B DEBOUNCE_DIS3 Debounce disable

0x2D GPIO_PULL2 GPIO pull disable

Rev. C | Page 15 of 28

ADP5588 Data Sheet

0x32

CMP_CONFG_SENS2

Sensor 2 comparator configuration register

AUTO_INC

7

I2C autoincrement. Burst read is supported; burst write is not supported.

Address Register Name Description

0x2E GPIO_PULL3 GPIO pull disable 0x2F Not used Not used 0x30 CMP_CFG_STAT Comparator configuration and status register 0x31 CMP_CONFG_SENS1 Sensor 1 comparator configuration register

0x33 CMP1_LVL2_TRIP L2 light sensor reference level (output falling for Sensor 1) 0x34 CMP1_LVL2_HYS L2 light sensor hysteresis (active when output rising) for Sensor 1 0x35 CMP1_LVL3_TRIP L3 light sensor reference level (output falling for Sensor 1) 0x36 CMP1_LVL3_HYS L3 light sensor hysteresis (active when output rising) for Sensor 1 0x37 CMP2_LVL2_TRIP L2 light sensor reference level (output falling for Sensor 2) 0x38 CMP2_LVL2_HYS L2 light sensor hysteresis (active when output rising) for Sensor 2 0x39 CMP2_LVL3_TRIP L3 light sensor reference level (output falling for Sensor 2) 0x3A CMP2_LVL3_HYS L3 light sensor hysteresis (active when output rising) for Sensor 2 0x3B CMP1_ADC_DAT_R1 Comparator 1 ADC Data Register 1 0x3C CMP1_ADC_DAT_R2 Comparator 1 ADC Data Register 2 0x3D CMP2_ADC_DAT_R1 Comparator 2 ADC Data Register 1 0x3E CMP2_ADC_DAT_R2 Comparator 2 ADC Data Register 2

REGISTER DESCRIPTIONS

Table 18. DEV_ID—Register 0x00 (Device ID)

Register Name Register Description Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

DEV_ID Device ID[3:0], MFG ID[7:4] MFID3 MFID2 MFID1 MFID0 DID3 DID2 DID1 DID0

Table 19. CFG—Register 0x01 (Configuration Register 1)

Field Bit Description

1: I2C autoincrement is on. 0: I2C autoincrement is off.

GPIEM_CFG 6 GPI event mode configuration.

1: GPI events are not tracked when the keypad is locked. 0: GPI events are tracked when the keypad is locked.

OVR_FLOW_M 5 Overflow mode.

1: Overflow mode is on; register overflow data shifts in, starting at the last event and losing first event data. 0: Overflow mode is off; register overflow data is lost.

INT_CFG 4 Interrupt configuration.

1: Processor interrupt deasserts for 50 μs and reasserts with pending key events. 0: Processor interrupt remains asserted when host tries to clear interrupt while there is a pending key event.

OVR_FLOW_IEN 3 Overflow interrupt enable.

1: Overflow interrupt is enabled. 0: Overflow interrupt is disabled.

K_LCK_IM 2 Keypad lock interrupt mask.

1: Keypad lock interrupt is enabled. 0: Keypad lock interrupt is disabled.

GPI_IEN 1 GPI interrupt enable.

1: GPI interrupt is enabled. 0: GPI interrupt is disabled.

KE_IEN 0 Key events interrupt enable.

1: Key events interrupt is enabled. 0: Key events interrupt is disabled.

Rev. C | Page 16 of 28

Data Sheet ADP5588

KEC1

[3:0]

Key event count of key event register.

KEY_EVENTE2

Key Event Register B status (KE[6:0] = Key number),

KE7

KE6

KE5

KE4

KE3

KE2

KE1

KE0

Table 20. INT_STAT—Register 0x02 (Interrupt Status Register)

Field Bit Description

CMP2_INT 5 Comparator interrupt status. When set, write 1 to clear.

1: Comparator 2 interrupt is detected. 0: Comparator 2 interrupt is not detected.

CMP1_INT 4 Comparator interrupt status. When set, write 1 to clear.

1: Comparator 1 interrupt is detected. 0: Comparator 1 interrupt is not detected.

OVR_FLOW_INT1 3 Overflow interrupt status. When set, write 1 to clear.

1: Overflow interrupt is detected. 0: Overflow interrupt is not detected.

K_LCK_INT2 2 Keylock interrupt status. When set, write 1 to clear.

1: Keylock interrupt is detected.

GPI_INT

KE_INT

1

2

3

1, 3

1 GPI interrupt status. When set, write 1 to clear.

1, 3

The KE_INT, GPI_INT, and OVR_FLOW_INT bits reflect the status of the interrupts when the interrupt types are enabled even if the processor interrupt is masked. The K_LCK_INT bit is the interrupt to the processor when the keypad lock sequence is triggered. If there is a pending key event or GPI interrupt in their respective registers, KE_INT does not clear until the FIFO is empty, and the GPI_INT bit does not clear until the

cause of the interrupt is resolved. The host must write a 1 to the INT bits to clear.

0 Key events interrupt status. When set, write 1 to clear.

0: Keylock interrupt is not detected.

1: GPI interrupt is detected. 0: GPI interrupt is not detected.

1: Key events interrupt is detected. 0: Key events interrupt is not detected.

Table 21. KEY_LCK_EC_STAT—Register 0x03 (Keylock and Event Counter Register)

Field Bit Description

K_LCK_EN [6] 0: Lock feature is disabled.

1: Lock feature is enabled.

LCK2, LCK1 [5:4] Keypad lock status[1:0] (00 = unlocked; 11 = locked; read only bits).

1

The KEC bit indicates the key event count of key event registers that have values in the bit (KEC(0000) = 0 events, KEC(0001) = 1 event, KEC(1010) = 10 events. As the

key events are read and cleared, the state machine automatically reduces the event count on KEC.

Table 22. KEY_EVENTx—Register 0x04 to Register 0x0D (Key Event Register A to Key Event Register J)1

Register Name Register Description Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

KEY_EVENTA (Register 0x04)

KEY_EVENTB (Register 0x05)

KEY_EVENTC (Register 0x06)

KEY_EVENTD (Register 0x07)

(Register 0x08)

KEY_EVENTF (Register 0x09)

KEY_EVENTG (Register 0x0A)

KEY_EVENTH (Register 0x0B)

Key Event Register A status (KE[6:0] = Key number), KP[7] = 0: released, 1: pressed (cleared on read)

Key Event Register B status (KE[6:0] = Key number), KP[7 ]= 0: released, 1: pressed (cleared on read)

Key Event Register C status (KE[6:0] = Key number), KP[7] = 0: released, 1: pressed (cleared on read)

Key Event Register B status (KE[6:0] = Key number), KP[7] = 0: released, 1: pressed (cleared on read)

KP[7]= 0: released, 1: pressed (cleared on read) Key Event Register B status (KE[6:0] = Key number),

KP[7] = 0: released, 1: pressed (cleared on read) Key Event Register B status (KE[6:0] = Key number),

KP[7] = 0: released, 1: pressed (cleared on read)

KA7 KA6 KA5 KA4 KA3 KA2 KA1 KA0

KB7 KB6 KB5 KB4 KB3 KB2 KB1 KB0

KC7 KC6 KC5 KC4 KC3 KC2 KC1 KC0

KD7 KD6 KD5 KD4 KD3 KD2 Kd1 KD0

KF7 KF6 KF5 KF4 KF3 KF2 KF1 KF0

KG7 KG6 KG5 KG4 KG3 KG2 KG1 KG0

KH7 KH6 KH5 KH4 KH3 KH2 KH1 KH0

Rev. C | Page 17 of 28

ADP5588 Data Sheet

Register Name

Register Description

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

GPIO_INT_STAT1

GPIO interrupt status (used to check

R7IS

R6IS

R5IS

R4IS

R3IS

R2IS

R1IS

R0IS

GP IO_DAT_STAT1

GPIO data status (shows GPIO state

R7DS

R6DS

R5DS

R4DS

R3DS

R2DS

R1DS

R0DS

Register Name Register Description Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

KEY_EVENTI (Register 0x0C)

KEY_EVENTJ (Register 0x0D)

1

Data in key events is provided as a FIFO, where data is sequentially provided on each read, regardless of an event register read. The user can read register Event A only

for an event count or can read registers sequentially.

2

KE[6:0] reflects the value 1 to 80 for key press events and the value 97 to 114 for GPI events. For KE[7:0], 0 = key released event, 1 = key pressed event. For GPIEM_CFG,

0 reflects a change in the GPI from GPI_INT_LVL = true to GPI_INT_LVL = false; 1 reflects a change in the GPI in which the GPI_INT_LVL condition becomes true.

Key Event Register B status (KE[6:0] = Key number), KP[7] = 0: released, 1: pressed (cleared on read)

Table 23. KP_LCK_TMR—Register 0x0E (Keypad Unlock 1 to Keypad Unlock 2 Timer)

KI7 KI6 KI5 KI4 KI3 KI2 KI1 KI0

KJ7 KJ6 KJ5 KJ4 KJ3 KJ2 KJ1 KJ0

KP_LCK_TMR (Register 0x0E)

1

When the keypad lock interrupt mask timer is enabled, the user must press two specific keys before a keylock interrupt is generated or keypad events are recorded.

After the keypad is locked, the first time that the user presses any key, a key event interrupt is generated. No additional interrupt is generated unless both unlock key sequences are correct; then a keylock interrupt is generated. When the interrupt mask timer is disabled (0), an interrupt is generated only when the correct full unlock sequence is completed.

2

The Unlock 1 and Unlock 2 timer keys can be either a key sequence or GPIEM_CFG sequence. The unlock timer keys can be programmed with any value of the keys in

the keypad matrix or any GPI values that are part of the key event table. The keylock enable bit (Bit 6, Register 0x03) must be set to lock the keypad.

Keypad UnLock 1 to Keypad UnLock 2 timer[2:0] (0: disabled, 1 sec to 7 sec) Keypad Lock Interrupt Mask Timer[7:3] (0: disabled, 0 sec to 31 sec)

1, 2

KIMT7 KIMT6 KIMT5 KIMT4 KIMT3 KLLT2 KLLT1 KLLT0

Table 24. UNLOCK1—Register 0x0F (Unlock Key 1)

Register Name Register Description Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

UNLOCK1 (Register 0x0F)

Unlock Key 1[6:0] (contains key number for Unlock Key 1; 0: disabled)

N/A ULK6 ULK5 ULK4 ULK3 ULK2 ULK1 ULK0

Table 25. UNLOCK2—Register 0x10 (Unlock Key 2)

Register Name Register Description Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

UNLOCK2 (Register 0x10)

Unlock Key 2[6:0] (contains key number for Unlock Key 2; 0: disabled)

N/A ULK6 ULK5 ULK4 ULK3 ULK2 ULK1 ULK0

Table 26. GPIO_INT_STATx—Register 0x11 to Register 0x13 (GPIO Interrupt Status)

Register Name Register Description Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

(Register 0x11) GPIO_INT_STAT2

(Register 0x12) GPIO_INT_STAT3

(Register 0x13)

GPIO interrupt status, cleared on read) GPIO interrupt status (used to check

GPIO interrupt status, cleared on read)

C7IS C6IS C5IS C4IS C3IS C2IS C1IS C0IS

N/A N/A N/A N/A N/A N/A C9IS C8IS

Table 27. GPIO_DAT_STATx—Register 0x14 to Register 0x16 (GPIO Data Status)

Register Name Register Description Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

(Register 0x14) GP IO_DAT_STAT2

(Register 0x15) GP IO_DAT_STAT3

(Register 0x16)

when read for inputs) GPIO data status (shows GPIO state

when read for inputs)

C7DS C6DS C5DS C4DS C3DS C2DS C1DS C0DS

N/A N/A N/A N/A N/A N/A C9DS C8DS

Rev. C | Page 18 of 28

Data Sheet ADP5588

(Register 0x1A)

GP inputs only)

Register Name

Register Description

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

1: GPI part of event FIFO (R0 to R7)

Table 28. GPIO_DAT_OUTx—Register 0x17 to Register 0x19 (GPIO Data Out)

Register Name Register Description Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

GPIO_DAT_OUT1 (Register 0x17)

GPIO_DAT_OUT2 (Register 0x18)

GPIO_DAT_OUT3 (Register 0x19)

GPIO data out (GPIO data to be written to GPIO out driver, inputs are not affected). This is needed so that the value can be written prior to being set as an output.

Table 29. GPIO_INT_ENx—Register 0x1A to Register 0x1C (GPIO Interrupt Enable)

Register Name Register Description Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

GPIO_INT_EN1

GPIO interrupt enable (enables interrupts for

R7DO R6DO R5DO R4DO R3DO R2DO R1DO R0DO

C7DO C6DO C5DO C4DO C3DO C2DO C1DO C0DO

N/A N/A N/A N/A N/A N/A C9DO C8DO

R7IE R6IE R5IE R4IE R3IE R2IE R1IE R0IE

GPIO_INT_EN2 (Register 0x1B)

GPIO_INT_EN3 (Register 0x1C)

GPIO interrupt enable (enables interrupts for GP inputs only)

C7IE C6IE C5IE C4IE C3IE C2IE C1IE C0IE

N/A N/A N/A N/A N/A N/A C9IE C8IE

Table 30. KP_GPIOx—Register 0x1D to Register 0x1F (Keypad or GPIO Selection)

KP_GPIO1 (Register 0x1D)

KP_GPIO2 (Register 0x1E)

KP_GPIO3 (Register 0x1F)

Keypad or GPIO selection 0: GPIO 1: KP matrix

R7 R6 R5 R4 R3 R2 R1 R0

C7 C6 C5 C4 C3 C2 C1 C0

N/A N/A N/A N/A N/A N/A C9 C8

Table 31. GPI_EM_REGx—Register 0x20 to Register 0x22 (GPI Event Mode 1 to GPI Event Mode 3)

Register Name Register Description Bit 7 Bit 6 Bit Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

GPI_EM_REG1 (Register 0x20)

GPI_EM_REG2 (Register 0x21)

GPI_EM_REG3 (Register 0x22)

GPI Event Mode Register 1 0: GPI not part of event FIFO

GPI Event Mode Register 2 0: GPI not part of event FIFO 1: GPI part of event FIFO (C0 to C7)

GPI Event Mode Register 3 0: GPI not part of event FIFO 1: GPI part of event FIFO (C8 to C9)

R7_EM R6_EM R5_EM R4_EM R3_EM R2_EM R1_EM R0_EM

C7_EM C6_EM C5_EM C4_EM C3_EM C2_EM C1_EM C0_EM

NA NA NA NA NA NA C9_EM C8_EM

Rev. C | Page 19 of 28

ADP5588 Data Sheet

Table 32. GPIO_DIRx—Register 0x23 to Register 0x25 (GPIO Data Direction)

Register Name Register Description Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

GPIO_DIR1 (Register 0x23)

GPIO_DIR2 (Register 0x24)

GPIO_DIR3 (Register 0x25)

GPIO data direction 0: GPIO 1: Output

Table 33. GPIO_INT_LVLx—Register 0x26 to Register 0x28 (GPIO Edge/Level Detect)

Register Name Register Description Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

GPIO_INT_LVL1 (Register 0x26)

GPIO_INT_LVL2 (Register 0x27)

GPIO_INT_LVL3 (Register 0x28)

GPIO INT level detect 0: Low 1: High

R7D R6D R5D R4D R3D R2D R1D R0D

C7D C6D C5D C4D C3D C2D C1D C0D

N/A N/A N/A N/A N/A N/A C9D C8D

R7IL R6IL R5IL R4IL R3IL R2IL R1IL R0IL

C7IL C6IL C5IL C4IL C3IL C2IL C1IL C0IL

N/A N/A N/A N/A N/A N/A C9IL C8IL

Table 34. DEBOUNCE_DISx—Register 0x29 to Register 0x2B (Debounce Disable)

Register Name Register Description Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

DEBOUNCE_DIS1 (Register 0x29)

DEBOUNCE_DIS2 (Register 0x2A)

DEBOUNCE_DIS3 (Register 0x2B)

Debounce disable (inputs) 0: Enabled 1: Disabled

R7DD R6DD R5DD R4DD R3DD R2DD R1DD R0DD

C7DD C6DD C5DD C4DD C3DD C2DD C1DD C0DD

N/A N/A N/A N/A N/A N/A C9DD C8DD

Table 35. GPIO_PULLx—Register 0x2C to Register 0x2E (GPIO Pull Disable)

Register Name Register Description Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

GPIO_PULL1 (Register 0x2C)

GPIO_PULL2 (Register 0x2D)

GPIO_PULL3 (Register 0x2E)

GPIO pull disable (remove pull-ups from inputs) 0: Pull enabled 1: Pull disabled

R7PD R6PD R5PD R4PD R3PD R2PD R1PD R0PD

C7PD C6PD C5PD C4PD C3PD C2PD C1PD C0PD

N/A N/A N/A N/A N/A N/A C9PD C8PD

Table 36. Register 0x2F

Field Bit Description

Not Used N/A Not used

Rev. C | Page 20 of 28

Data Sheet ADP5588

COMPARATOR REGISTER DESCRIPTIONS

Table 37. CMP_CFG_STAT—Register 0x30 (Comparator Configuration and Status Register)

Field Bit Description

CMP2_L3_OUT 7

CMP2_L2_OUT 6

CMP1_L3_OUT 5

CMP1_L2_OUT 4

CMP2_IEN 3

CMP1_IEN 2

CMP2_EN 1

CMP1_EN 0

Sensor 2 Comparator L3 output. 0: Ambient light is greater than Level 3 (dark). 1: L3_CMP has detected a change in ambient light from Level 2 (office) to L3 (dark).

Sensor 2 Comparator L2 output. 0: Ambient light is greater than Level 2 (office). 1: L2_CMP has detected a change in ambient light from Level 1 (outdoor) to L2 (office).

Sensor 1 Comparator L3 output. 0: Ambient light is greater than Level 3 (dark). 1: L3_CMP has detected a change in ambient light from Level 2 (office) to L3 (dark).

Sensor 1 Comparator L2 output. 0: Ambient light is greater than Level 2 (office). 1: L2_CMP has detected a change in ambient light from Level 1 (outdoor) to L2 (office).

Sensor 2 comparator interrupt. 0: Interrupt disabled. 1: Interrupt enabled.

Sensor 1 comparator interrupt. 0: Interrupt disabled. 1: Interrupt enabled.

Sensor 2 comparator input. 0: Input disabled. 1: Input enabled.

Sensor 1 comparator input. 0: Input disabled. 1: Input enabled.

Table 38. CMP_CONFG_SENS1—Register 0x31 (Sensor 1 Comparator Configuration Register)

Field Bit Description

[7:6] Not used. FILT (2-0) [5:3] Programs the number of consecutive measurements required to transition the L2 and L3 levels.

FILT Number Required Approximate Time (sec)

000 1 0.08 001 2 0.16 010 4 0.32 011 8 0.64 100 16 1.28 101 32 2.56 110 64 5.12 111 128 10.24

FORCE_RD 2

1: Forces a read of the light sensor; reset by the internal state machine after conversion is complete and L2_OUT and L3_OUT are valid.

1

L3_EN 1 1: Enables the L3 comparator for Sensor 1 input.

0: Disables the L3 comparator for Sensor 1 input.

L2_EN 0 1: Enables the L2 comparator for Sensor 1 input.

0: Disables the L2 comparator for Sensor 1 input. Note that the L3 comparator has priority over the L2 comparator.

1

When the software forces a conversion, the state machine clears the forced bit after the conversion is done and the proper registers have been updated.

Rev. C | Page 21 of 28

ADP5588 Data Sheet

001 2 0.16

Table 39. CMP_CONFG_SENS2—Register 0x32 (Sensor 2 Comparator Configuration Register)

Field Bit Description

[7:6] Not used. FILT (2-0) [5:3] Programs the number of consecutive measurements required to transition the L2 and L3 levels.

FI LT Number Required Approximate Time (sec)

000 1 0.08

010 4 0.32

011 8 0.64

100 16 1.28

101 32 2.56

110 64 5.12

111 128 10.24

FORCE_RD 2 1: Forces a read of the light sensor; reset by the internal state machine after conversion is complete and

L2_OUT and L3_OUT are valid.

L3_EN 1 1: Enables the L3 comparator for Sensor 2 input.

0: Disables the L3 comparator for Sensor 2 input.

L2_EN 0 1: Enables the L3 comparator for Sensor 2 input.

0: Disables the L3 comparator for Sensor 2 input. Note that the L3 comparator has priority over the L2 comparator.

1

When the software forces a conversion, the state machine clears the forced bit after the conversion is complete and the proper registers have been updated.

1

Table 40. CMP1_LVL2_TRIP—Register 0x33 (L2 Light Sensor Reference Level (Output Falling for Sensor 1)

Field Bit Description

L2_T7 to L2_T0 [7:0] Sensor 1 comparator Level 2 (Office) reference. If the comparator input is below this trip point, the

comparator trips and enters Level 2 (office) mode and L2_OUT is set. The programmable range is from 0 μA to 1000 μA (0 lux to 2550 lux) in steps of 4 μA.

Table 41. CMP1_LVL2_HYS—Register 0x34 (L2 Light Sensor Hysteresis (Active When Output Rising) for Sensor 1)

Field Bit Description

L2_H7 to L2_H0 [7:0] Sensor 1 comparator Level 2 (Office) hysteresis. If the comparator input is above L2_TRP + L2_HYS, the

comparator trips and enters Level 1 (outdoor) mode and L2_OUT is cleared. The programmable range is from 0 μA to 1000 μA (0 lux to 2550 lux) in steps of 4 μA.

Table 42. CMP1_LVL3_TRIP—Register 0x35 (L3 Light Sensor Reference Level (Output Falling for Sensor 1)

Field Bit Description

L3_T7 to L3_T0 [7:0] Sensor 1 comparator Level 3 (Dark) reference. If the comparator input is below L3_TRP, the comparator trips

and enters Level 3 (dark) mode and L3_OUT is set. The programmable range is from 0 μA to 127.5 μA (0 lux to

318.75 lux) in steps of 0.5 μA.

Table 43. CMP1_LVL3_HYS—Register 0x36 (L3 Light Sensor Hysteresis (Active When Output Rising) for Sensor 1)

Field Bit Description

L3_H [7:0] Sensor 1 comparator Level 3 (Dark) hysteresis. If the comparator input is above L3_TRP + L3_HYS, the

comparator trips and enters Level 2 (office) mode and L3_OUT is cleared. The programmable range is from 0 μA to 127.5 μA (0 lux to 318.75 lux) in steps of 0.5 μA.

Rev. C | Page 22 of 28

Data Sheet ADP5588

Field

Bit

Description

CMP1_ADC_DAT

Comparator ADC Data Register

N/A

N/A ADC12

ADC11

ADC10

ADC9

ADC8

Table 44. CMP2_LVL2_TRIP—Register 0x37 (L2 Light Sensor Reference Level (Output Falling for Sensor 2)

Field Bit Description

L2_T7 to L2_T0 [7:0] Sensor 2 comparator Level 2 (Office) reference. If the comparator input is below this trip point, the

comparator trips and enters Level 2 (office) mode and L2_OUT is set. The programmable range is from 0 μA to 1000 μA (0 lux to 2550 lux) in steps of 4 μA.

Table 45. CMP2_LVL2_HYS—Register 0x38 (L2 Light Sensor Hysteresis (Active When Output Rising) for Sensor 2)

Field Bit Description

L2_H7 to L2_H0 [7:0] Sensor 2 comparator Level 2 (Office) hysteresis. If the comparator input is above L2_TRP + L2_HYS, the

comparator trips and enters Level 1 (outdoor) mode and L2_OUT is cleared. The programmable range is from 0 μA to 1000 μA (0 lux to 2550 lux) in steps of 4 μA.

Table 46. CMP2_LVL3_TRIP—Register 0x39 (L3 Light Sensor Reference Level (Output Falling for Sensor 2)

Field Bit Description

L3_T7 to L3_T0 [7:0] Sensor 2 Comparator Level 3 (Dark) Reference. If the comparator input is below L3_TRP, the comparator trips

and enters Level 3 (dark) mode and L3_OUT is set. The programmable range is from 0 μA to 127.5 μA (0 lux to

318.75 lux) in steps of 0.5 μA.

Table 47. CMP2_LVL3_HYS—Register 0x3A (L3 Light Sensor Hysteresis (Active When Output Rising) for Sensor 2)

L3_H [7:0] Sensor 2 comparator Level 3 (Dark) hysteresis. If the comparator input is above L3_TRP + L3_HYS, the

comparator trips and enters Level 2 (office) mode and L3_OUT is cleared. The programmable range is from 0 μA to 127.5 μA (0 lux to 318.75 lux) in steps of -.5 μA.

Table 48. CMP1_ADC_DAT_R1—Register 0x3B (Comparator 1 ADC Data Register 1)

Register Name Register Description Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

CMP1_ADC_DAT Comparator ADC data register,

NA NA NA ADC12 ADC11 ADC10 ADC9 ADC8

Bits[7:0]

Table 49. CMP1_ADC_DAT_R2—Register 0x3C (Comparator 1 ADC Data Register 2)1

Register Name Register Description Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

CMP1_ADC_DAT Comparator ADC data register,

ADC7 ADC6 ADC5 ADC4 ADC3 ADC2 ADC1 ADC0

Bits[7:0]

1

Read-only register; contains the most current 13-bit ADC data of the comparator for Sensor 1.

Table 50. CMP2_ADC_DAT_R1—Register 0x3D (Comparator 2 ADC Data Register 1)

Register Name Register Description Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

[7:0]

Table 51. CMP2_ADC_DAT_R2—Register 0x3E (Comparator 2 ADC Data Register 2)1

Register Name Register Description Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

CMP1_ADC_DAT Comparator ADC data register,

ADC7 ADC6 ADC5 ADC ADC3 ADC2 ADC1 ADC0

Bits[7:0]

1

Read-only register; contains the most current 13-bit ADC data of the comparator for Sensor 2.

Rev. C | Page 23 of 28

ADP5588 Data Sheet

CONTROL

REGISTERS

HOST

PROCESSOR

CONTROL

INTERFACE

REF

VOLTAGE

C9

C8

R7R6R5R4R3R2R1R0C0C1C2C3C4C5C6

C7

C9

C8

ENABLE 2 (GP O)

BACKLIGHT

ENABLE (GPO)

A0A1A2A3

A4A5A6A7

B0B1B2B3B4B5B6B7 C0C1C2C3C4C5C6C7 D0D1D2D3D4D5D6D7 E0E1E2E3E4E5E6E7 F0F1F2F3

F4F5F6F7

G0G1G2G3G4G5G6G7

H0H1H2H3H4H5H6H7

I0I1I2I3I4I5I6I7

J0J1J2J3J4J5J6J7

SCL

SDA

V

CC

GND

V

CC

SCL

GPL1

GPL2

SDA RST INT

19

21

23

22

18

17

20

24

1 2 3 4 5 6 7

8

9 10 11 12 13 14 15 16

REF

VOLTAGE

0.1µF

V

CC

V

CC

07673-022

BACKLIGHT

DRIVER

PWM OUTPUT

ADP5588

V

CC

RST

INT

1

V

= 1.8 V to 3.0 V

55

μA

APPLICATIONS INFORMATION

Figure 17. ADP5588 Detailed Application Block Diagram

APPLICATIONS OVERVIEW

The ADP5588 is designed to complement host processors in a variety of ways. Its versatility makes it the ideal solution for mobile platforms that require extended keypads and GPIO expanders. The programmable registers give the designer the flexibility to configure any or all its GPIOs in a variety of ways. Figure 17 shows a detailed application diagram.

KEYPAD CURRENT

Keypad current drain varies based on how many keys and how many rows and columns are pressed during multiple key presses. Table 52 shows typical current drain for a single press and for two key presses.

Table 52. Typical Current Drain

Key Presses Conditions

2 V

1

TA = TJ = −40°C to +85°C.

CC

1

= 1.8 V to 3.0 V 100 μA

Typical Unit

Rev. C | Page 24 of 28

BACKLIGHT CONTROL APPLICATION

Although the ADP5588 is not designed with a backlight driver, the built-in light sensor comparator inputs, with programmable registers and trip points, give the backlight designer all the necessary tools to control the backlight based on lighting conditions or environment. With a few I can program the device to monitor lighting conditions and trigger an interrupt based on preset trip points. Once programmed, the state machine uses these trip points and hysteresis values to alert the microprocessor of any change in lighting conditions. In addition to the L2_OUT and L3_OUT bits, four additional registers (Register 0x3B through Register 0x3E, two registers per light sensor) provide detailed accounts of the internal ADC due to light condition changes. The ADC has a full-scale current of 1000 μA and a dynamic range of 8000, which translates to 0.125 μA or 0.3125 lux per step. These two corresponding registers per sensor form a 13-bit register that can be read to provide detailed translation of the light sensor input at any instant.

2

C commands, the designer

Data Sheet ADP5588

HOST

PROCESSOR

BACKLIGHT

DRIVER

PWM

BACKLIGHT

EXPANDED

GPIOs

KEYPAD MATRI X

BACKLIGHT ENABLE

ADP5588

A0 A1 A2 A3

A4 A5 A6 A7

B0 B1 B2 B3 B4 B5 B6 B7

C0 C1 C2 C3 C4 C5 C6 C7

D0 D1 D2 D3 D4 D5 D6 D7

E0 E1 E2 E3 E4 E5 E6 E7

F0 F1 F2 F3 F4 F5 F6 F7

G0 G1 G2 G3 G4 G5 G6 G7

H0 H1 H2 H3 H4 H5 H6 H7

I0 I1 I2 I3 I4 I5 I6 I7

J0 J1 J2 J3 J4 J5 J6 J7

V

CC

LIGHT

SENSORS

I

2

C

RST

INT

07673-023

Figure 18. Integration Block Diagram

Rev. C | Page 25 of 28

ADP5588 Data Sheet

0.50

BSC

0.50

0.40

0.30

0.25

0.20

COMPLIANT

TO

JEDEC STANDARDS MO-220-WGGD-8.

072809A

BOTTOM VIEWTOPVIEW

EXPOSED

PAD

PIN 1 INDICATOR

4.10

4.00 SQ

3.90

SEATING

PLANE

0.80

0.75

0.70

0.05 MAX

0.02 NOM

0.20 REF

0.25 MIN

COPLANARITY

0.08

PIN 1

INDICATOR

1

24

7

12

13

18

19

6

FOR PROPER CONNECTION OF THE EXPOSED PAD, REFER TO THE PIN CONFIGURATION AND FUNCTION DESCRIPTIONS SECTION OF THIS DATA SHEET.

2.20

2.10 SQ

2.00

OUTLINE DIMENSIONS

Figure 19. 24-Lead Lead Frame Chip Scale Package [LFCSP_WQ]

4 mm × 4 mm Body, Very Very Thin Quad

(CP-24-10)

Dimensions shown in millimeters

ORDERING GUIDE

Model1 Temperature Range Package Description Package Option

ADP5588ACPZ-R7 −40°C to +85°C 24-Lead Lead Frame Chip Scale Package [LFCSP_WQ] CP-24-10 ADP5588-EVALZ Evaluation Board

1

Z = RoHS Compliant Part.

Rev. C | Page 26 of 28

Data Sheet ADP5588

NOTES

Rev. C | Page 27 of 28

ADP5588 Data Sheet

NOTES

registered trademarks are the property of their respective owners. D07673-0-2/12(C)

Rev. C | Page 28 of 28

Datasheet ADP5588 Datasheet (ANALOG DEVICES)

Specifications and Main Features

Frequently Asked Questions

User Manual

FEATURES

FUNCTIONAL BLOCK DIAGRAM

APPLICATIONS

GENERAL DESCRIPTION

TABLE OF CONTENTS

REVISION HISTORY

SPECIFICATIONS

DC ELECTRICAL CHARACTERISTICS

ABSOLUTE MAXIMUM RATINGS

THERMAL RESISTANCE

ESD CAUTION

PIN CONFIGURATION AND FUNCTION DESCRIPTIONS

THEORY OF OPERATION

KEYPAD OPERATION

Key Event Tracking

Key Event Overflow

Autoincrement

Key Event Interrupt

Keypad Lock/Unlock Feature

GENERAL-PURPOSE INPUTS AND OUTPUTS

General Purpose Inputs (GPI)

GPI Events

50 Microsecond Interrupt Configuration

Debouncing

General Purpose Outputs (GPOs)

Power-On Reset

Ambient Light Sensing

Light Sensor Inputs

L2 Comparator

L3 Comparator

Photosensor Operation

Comparator Interrupt

I2C PROGRAMMING AND DIGITAL CONTROL

REGISTERS

REGISTER DESCRIPTIONS

COMPARATOR REGISTER DESCRIPTIONS

APPLICATIONS INFORMATION

APPLICATIONS OVERVIEW

KEYPAD CURRENT

BACKLIGHT CONTROL APPLICATION

OUTLINE DIMENSIONS

ORDERING GUIDE