Rainbow Electronics MAX6965 User Manual
General Description
The MAX6965 I2C™-compatible serial interfaced peripheral provides microprocessors with nine additional output ports. Each output is an open-drain current-sinking
output rated to 50mA at 7V. All outputs are capable of
driving LEDs, or providing logic outputs with external
resistive pullup up to 7V.
Eight-bit PWM current control is also integrated. Four of
the bits are global control and apply to all LED outputs
to provide coarse adjustment of current from fully off to
fully on with 14 intensity steps. Additionally each output
then has an individual 4-bit control, which further
divides the globally set current into 16 more steps.
Alternatively, the current control can be configured as a
single 8-bit control that sets all outputs at once.
Each output has independent blink timing with two blink
phases. LEDs can be individually set to be either on or off
during either blink phase, or to ignore the blink control.
The blink period is controlled by an external clock (up to
1kHz) on BLINK or by a register. The BLINK input can also
be used as a logic control to turn the LEDs on and off, or
as a general-purpose input (GPI).
The MAX6965 is controlled through a 2-wire I
2
C serial
interface, and can be configured to one of four I2C
addresses.
Applications
Features
♦ 400kbps, 2-Wire Serial Interface, 5.5V Tolerant
♦ 2V to 3.6V Operation
♦ Overall 8-Bit PWM LED Intensity Control
Global 16-Step Intensity Control
Plus Individual 16-Step Intensity Controls
♦ Two-Phase LED Blinking
♦ High Port Output Current—Each Port 50mA (max)
♦ RST Input Clears the Serial Interface and
Restores Power-Up Default State
♦ Outputs are 7V-Rated Open Drain
♦ Low Standby Current (1.2µA (typ), 3.3µA (max))
♦ Tiny 3mm x 3mm, Thin QFN Package
♦ -40°C to +125°C Temperature Range
MAX6965
9-Output LED Driver with Intensity Control
________________________________________________________________ Maxim Integrated Products 1
Pin Configurations
MAX6965
O0
O1
O2
O3
O4
O5
V+
3.3V
µC
SDA
SCL
SDA
I/O
I/O
AD0
6V
O6
O7
O8
SCL
RELAY
RELAY
GND
7V
0.047µF
RST
BLINK
RELAY
Typical Application Circuit
19-3058; Rev 0; 10/03
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
Ordering Information
Pin Configurations continued at end of data sheet.
LCD Backlights
LED Status Indication
Keypad Backlights
RGB LED Drivers
Purchase of I2C components of Maxim Integrated Products, Inc.,
or one of its sublicensed Associated Companies, conveys a
license under the Philips I
2
C Patent Rights to use these compo-
nents in an I
2
C system, provided that the system conforms to the
I
2
C Standard Specification as defined by Philips.
PART TEMP RANGE PIN-PACKAGE
MAX6965ATE -40°C to +125°C
MAX6965AEE -40°C to +125°C 16 QSOP —
16 Thin QFN
3mm x 3mm x 0.8mm
TOP
MARK
AAW
TOP VIEW
AD0
O0
O1
O2
RST
BLINK
V+
SDA
16
15 14 13
1
2
3
4
MAX6965ATE
5678
O3
GND
QFN
O4
O5
SCL
12
O8
11
O7
10
O6
9
MAX6965
9-Output LED Driver with Intensity Control
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
Voltage (with respect to GND)
V+ .............................................................................-0.3V to +4V
SCL, SDA, AD0, BLINK, RST ...................................-0.3V to +6V
O0–O8 ......................................................................-0.3V to +8V
DC Current on O0 to O8 .....................................................55mA
DC Current on SDA.............................................................10mA
Maximum GND Current ....................................................190mA
Continuous Power Dissipation (T
A
= +70°C)
16-Pin QSOP (derate 8.3mW/°C over +70°C)..............666mW
16-Pin QFN (derate 14.7mW/°C over +70°C) ............1176mW
Operating Temperature Range (T
MIN
to T
MAX
) ...-40°C to +125°C
Junction Temperature......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
ELECTRICAL CHARACTERISTICS
(Typical Operating Circuit, V+ = 2V to 3.6V, TA= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at V+ = 3.3V, TA = +25°C.)
(Note 1)
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Operating Supply Voltage V+ 2.0 3.6 V
Output Load External Supply
Voltage
Standby Current
(Interface Idle, PWM Disabled)
Supply Current
(Interface Idle, PWM Enabled)
Supply Current
(Interface Running, PWM
Disabled)
Supply Current
(Interface Running, PWM
Enabled)
Input High Voltage
SDA, SCL, AD0, BLINK, RST
Input Low Voltage
SDA, SCL, AD0, BLINK, RST
Input Leakage Current
SDA, SCL, AD0, BLINK, RST
V
EXT
S C L and S D A at V + ; other
I
d i g i tal i np uts at V + or GN D ;
+
P WM i ntensi ty contr ol d i sab l ed
S C L and S D A at V + ; other
I
d i g i tal i np uts at V + or GN D ;
+
P WM i ntensi ty contr ol enab l ed
f
I
inputs at V+ or GND; PWM
+
intensity control disabled
f
I
inputs at V+ or GND; PWM
+
intensity control enabled
V
IH
V
IL
, IIL0 ≤ input voltage ≤ 5.5V -0.2 +0.2 µA
I
IH
Input Capacitance
SDA, SCL, AD0, BLINK, RST
= 400kHz; other digital
SCL
= 400kHz; other digital
SCL
TA = +25°C 1.2 2.3
TA = -40°C to +85°C 2.6
T
= T
MIN
to T
MAX
A
TA = +25°C 7 12.1
TA = -40°C to +85°C 13.3
T
= T
MIN
to T
MAX
A
TA = +25°C4076
TA = -40°C to +85°C78
T
= T
MIN
to T
MAX
A
TA = +25°C 51 110
TA = -40°C to +85°C 117
T
= T
MIN
to T
MAX
A
07V
3.3
14.4
80
122
0.7 ✕
V+
0.3 ✕
V+
8pF
µA
µA
µA
µA
V
V
MAX6965
9-Output LED Driver with Intensity Control
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(Typical Operating Circuit, V+ = 2V to 3.6V, TA= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at V+ = 3.3V, TA= + 25°C.)
(Note 1)
TIMING CHARACTERISTICS
(Typical Operating Circuit, V+ = 2V to 3.6V, TA= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at V+ = 3.3V, TA = +25°C.)
(Note 1)
Output Low Voltage
O0–O8
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
OL
V+ = 2.5V, I
V
V+ = 3.3V, I
Output Low-Voltage SDA V
PWM Clock Frequency f
OLSDAISINK
PWM
= 20mA
SINK
= 20mA
SINK
= 20mA
SINK
= 6mA 0.4 V
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
Serial Clock Frequency f
Bus Free Time Between a STOP and a START
Condition
Hold Time, Repeated START Condition t
Repeated START Condition Setup Time t
STOP Condition Setup Time t
Data Hold Time t
Data Setup Time t
SCL Clock Low Period t
SCL Clock High Period t
Rise Time of Both SDA and SCL Signals, Receiving t
Fall Time of Both SDA and SCL Signals, Receiving t
Fall Time of SDA Transmitting t
Pulse Width of Spike Suppressed t
Capacitive Load for Each Bus Line C
SCL
t
BUF
HD, STA
SU, STA
SU, STO
HD, DAT
SU, DAT
LOW
HIGH
F.TX
(Note 2) 0.9 µs
(Notes 3, 4)
R
(Notes 3, 4)
F
(Notes 3, 5)
(Note 6) 50 ns
SP
(Note 3) 400 pF
b
TA = +25°C 0.15 0.25
TA = -40°C to +85°C 0.29V+ = 2V, I
T
= T
MIN
to T
MAX
A
0.31
TA = +25°C 0.13 0.22
TA = -40°C to +85°C 0.25
= T
MIN
to T
MAX
T
A
0.27
TA = +25°C 0.12 0.22
TA = -40°C to +85°C 0.23
T
= T
MIN
to T
MAX
A
0.25
32 kHz
400 kHz
1.3 µs
0.6 µs
0.6 µs
0.6 µs
180 ns
1.3 µs
0.7 µs
20 +
0.1C
20 +
0.1C
20 +
0.1C
b
b
b
300 ns
300 ns
250 ns
V
MAX6965
9-Output LED Driver with Intensity Control
4 _______________________________________________________________________________________
__________________________________________Typical Operating Characteristics
(TA = +25°C, unless otherwise noted.)
TIMING CHARACTERISTICS (continued)
(Typical Operating Circuit, V+ = 2V to 3.6V, TA= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at V+ = 3.3V, TA = +25°C.)
(Note 1)
Note 1: All parameters tested at TA= +25°C. Specifications over temperature are guaranteed by design.
Note 2: A master device must provide a hold time of at least 300ns for the SDA signal (referred to V
IL
of the SCL signal) to bridge
the undefined region of SCL’s falling edge.
Note 3: Guaranteed by design.
Note 4: C
b
= total capacitance of one bus line in pF. tRand tFmeasured between 0.3 x VDDand 0.7 x VDD.
Note 5: I
SINK
≤ 6mA. Cb= total capacitance of one bus line in pF. tRand tFmeasured between 0.3 x VDDand 0.7 x VDD.
Note 6: Input filters on the SDA and SCL inputs suppress noise spikes less than 50ns.
PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS
RST Pulse Width t
Output Data Valid t
STANDBY CURRENT vs. TEMPERATURE
10
9
8
7
6
5
4
3
STANDBY CURRENT (µA)
2
1
0
V+ = 3.6V
PWM ENABLED
V+ = 2V
V+ = 2.7V
PWM ENABLED
V+ = 2V
PWM DISABLED
-40 125
TEMPERATURE (°C)
PWM ENABLED
V+ = 2.7V
PWM DISABLED
V+ = 3.6V
PWM
DISABLED
1109565 80-10 5 20 35 50-25
MAX6965 toc01
SUPPLY CURRENT (µA)
W
Figure 10 5 µs
DV
SUPPLY CURRENT vs. TEMPERATURE
(PWM DISABLED; f
70
60
50
40
30
20
10
0
-40 125
V+ = 3.6V
TEMPERATURE (°C)
= 400kHz)
SCL
V+ = 2.7V
V+ = 2V
1µs
SUPPLY CURRENT vs. TEMPERATURE
(PWM ENABLED; f
70
65
60
MAX6965 toc02
55
50
45
40
35
30
25
SUPPLY CURRENT (µA)
20
15
10
5
1109565 80-10 5 20 35 50-25
0
V+ = 3.6V
TEMPERATURE (°C)
SCL
V+ = 2.7V
V+ = 2V
= 400kHz)
MAX6965 toc03
1109565 80-10 5 20 35 50-25-40 125
PORT OUTPUT LOW VOLTAGE WITH 50mA
LOAD CURRENT vs. TEMPERATURE
0.6
(V)
0.5
OL
V+ = 2V
0.4
0.3
0.2
0.1
PORT OUTPUT LOW VOLTAGE V
0
V+ = 2.7V
V+ = 3.6V
TEMPERATURE (°C)
MAX6965 toc04
1109565 80-10 5 20 35 50-25-40 125
PORT OUTPUT LOW VOLTAGE WITH 20mA
LOAD CURRENT vs. TEMPERATURE
0.6
ALL OUTPUTS LOADED
(V)
0.5
OL
0.4
0.3
0.2
0.1
PORT OUTPUT LOW VOLTAGE V
0
-40 125
V+ = 2V
V+ = 2.7V
TEMPERATURE (°C)
V+ = 3.6V
PWM CLOCK FREQUENCY
vs. TEMPERATURE
1.050
1.025
MAX6965 toc05
1.000
0.975
0.950
PWM CLOCK FREQUENCY
0.925
1109580655035205-10-25
0.900
-40 125
V+ = 3.6V
V+ = 2.7V
NORMALIZED TO V+ = 3.3V, TA = +25°C
TEMPERATURE (°C)
MAX6965 toc06
V+ = 2V
1109580655035205-10-25
MAX6965
9-Output LED Driver with Intensity Control
_______________________________________________________________________________________ 5
Typical Operating Characteristics (continued)
(TA = +25°C, unless otherwise noted.)
Pin Description
SCOPE SHOT OF TWO OUTPUT PORTS
MASTER INTENSITY SET TO 1/15
OUTPUT 1 INDIVIDUAL INTENSITY
SET TO 1/16
OUTPUT 2 INDIVIDUAL INTENSITY
SET TO 15/16
2ms/div
MAX6965 toc07
PIN
QSOP QFN
OUTPUT 1
2V/div
OUTPUT 2
2V/div
NAME FUNCTION
SCOPE SHOT OF TWO OUTPUT PORTS
MASTER INTENSITY SET TO 14/15
OUTPUT 1 INDIVIDUAL INTENSITY
SET TO 1/16
OUTPUT 2 INDIVIDUAL INTENSITY
SET TO 14/15
2ms/div
MAX6965 toc08
OUTPUT 1
2V/div
OUTPUT 2
2V/div
(V)
V
0.35
0.30
0.25
0.20
OL
0.15
0.10
0.05
0
1 15 BLINK Input Port. Configurable as blink control or general-purpose input.
216RST
3 1 AD0
Reset Input. Active low clears the 2-wire interface and puts the device in same
condition as power-up reset.
Address Input. Sets device slave address. Connect to either GND, V+, SCL, or
SDA to give 4 logic combinations. See Table 1.
4–7, 9–13 2–5, 7–11 O0–O8 Output Ports. O0–O8 are open-drain outputs rated at 7V, 50mA.
8 6 GND Ground. Do not sink more than 190mA into the GND pin.
14 12 SCL I2C-Compatible Serial Clock Input
15 13 SDA I2C-Compatible Serial Data I/O
16 14 V+ Positive Supply Voltage. Bypass V+ to GND with a 0.047µF ceramic capacitor
— PAD Exposed Pad Exposed pad on packaged underside. Connect to GND.
SINK CURRENT vs. V
ONLY ONE OUTPUT LOADED
V+ = 2.7V
050
SINK CURRENT (mA)
V+ = 2V
OL
MAX6965 toc09
V+ = 3.6V
V+ = 3.3V
45403530252015105
MAX6965
Functional Overview
The MAX6965 is a general-purpose output (GPO)
peripheral that provides nine output ports, O0–O8, controlled through an I2C-compatible serial interface. All outputs sink loads up to 50mA connected to external
supplies up to 7V, independent of the MAX6965’s supply
voltage. The MAX6965 is rated for a ground current of
190mA, allowing all nine outputs to sink 20mA at the
same time. Figure 1 shows the output structure of the
MAX6965. The outputs default to logic high (high impedance unless external pullup resistors are used) on
power-up.
Output Control and LED Blinking
The blink phase 0 register sets the output logic levels of
the 8 outputs O0–O7 (Table 6). This register controls
the port outputs if the blink function is disabled. A duplicate register, the Blink Phase 1 register, is also used if
the blink function is enabled (Table 7). In blink mode,
the outputs can be flipped between using the blink
phase 0 register, and the blink phase 1 register using
hardware control (the BLINK input) and/or software
control (the blink flip flag in the configuration register)
(Table 4).
The 9th output, O8, is controlled through 2 bits in the
Configuration register, which provide the same static or
blink control as the other eight outputs (Table 4).
The logic level of the BLINK input may be read back
through the blink status bit in the configuration register
(Table 4). The BLINK input, therefore, may be used as
a general-purpose logic input (GPI port) if the blink
function is not required.
PWM Intensity Control
The MAX6965 includes an internal oscillator, nominally
32kHz, to generate PWM timing for LED intensity control. PWM intensity control can be enabled on an output-by-output basis, allowing the MAX6965 to provide
any mix of PWM LED drives and glitch-free logic outputs (Table 8). PWM can be disabled entirely, in which
case all outputs are static and the MAX6965 operating
current is lowest because the internal oscillator is
turned off.
PWM intensity control uses a 4-bit master control and 4
bits of individual control per output (Tables 11 and 12).
The 4-bit master control provides 16 levels of overall
intensity control, which applies to all PWM-enabled outputs. The master control sets the maximum pulse width
from 1/15 to 15/15 of the PWM time period. The individual settings comprise a 4-bit number, further reducing
the duty cycle to be from 1/16 to 15/16 of the time window set by the master control.
For applications requiring the same PWM setting for all
output ports, a single global PWM control can be used
instead of all the individual controls to simplify the control software and provide 240 steps of intensity control
(Tables 8 and 11).
9-Output LED Driver with Intensity Control
6 _______________________________________________________________________________________
Figure 1. Simplified Schematic of I/O Ports
Figure 2. 2-Wire Serial Interface Timing Details
OUTPUT
PORT
DATA FROM
SHIFT REGISTER
WRITE PULSE
REGISTER
D
FF
C
K
OUTPUT PORT
Q
REGISTER DATA
Q
I/O PIN
Q2
GND
SDA
t
STOP
CONDITION
BUF
SCL
t
HD,STA
START CONDITION
t
t
SU,DAT
t
LOW
t
HIGH
t
R
t
HD,DAT
t
F
SU,STA
REPEATED START CONDITION
t
HD,STA
t
SU,STO
START
CONDITION
User RAM
The MAX6965 includes a register byte, which is available as general-user RAM (Table 2). This byte is reset
to the value 0xFF on power-up and when the RST input
is taken low (Table 3).
Standby Mode
When the serial interface is idle and the PWM intensity
control is unused, the MAX6965 automatically enters
standby mode. If the PWM intensity control is used, the
operating current is slightly higher because the internal
PWM oscillator is running. When the serial interface is
active, the operating current also increases because
the MAX6965, like all I2C slaves, has to monitor every
transmission.
Serial Interface
Serial Addressing
The MAX6965 operates as a slave that sends and
receives data through an I2C-compatible 2-wire interface. The interface uses a serial data line (SDA) and a
serial clock line (SCL) to achieve bidirectional communication between master(s) and slave(s). A master (typically a microcontroller) initiates all data transfers to and
from the MAX6965 and generates the SCL clock that
synchronizes the data transfer (Figure 2).
The MAX6965 SDA line operates as both an input and
an open-drain output. A pullup resistor, typically 4.7kΩ,
is required on SDA. The MAX6965 SCL line operates
only as an input. A pullup resistor, typically 4.7kΩ, is
required on SCL if there are multiple masters on the 2wire interface, or if the master in a single-master system
has an open-drain SCL output.
Each transmission consists of a START condition
(Figure 3) sent by a master, followed by the MAX6965
7-bit slave address plus R/W bit, a register address
byte, one or more data bytes, and finally a STOP condition (Figure 3).
Start and Stop Conditions
Both SCL and SDA remain high when the interface is
not busy. A master signals the beginning of a transmission with a START (S) condition by transitioning SDA
from high to low while SCL is high. When the master
has finished communicating with the slave, it issues a
STOP (P) condition by transitioning SDA from low to
high while SCL is high. The bus is then free for another
transmission (Figure 3).
Bit Transfer
One data bit is transferred during each clock pulse.
The data on SDA must remain stable while SCL is high
(Figure 4).
Acknowledge
The acknowledge bit is a clocked 9th bit that the recipient uses to handshake receipt of each byte of data
(Figure 5). Thus, each byte transferred effectively
requires 9 bits. The master generates the 9th clock
pulse, and the recipient pulls down SDA during the
acknowledge clock pulse so the SDA line is stable low
MAX6965
9-Output LED Driver with Intensity Control
_______________________________________________________________________________________ 7
Figure 3. Start and Stop Conditions
Figure 4. Bit Transfer
Figure 5. Acknowledge
Figure 6. Slave Address
SDA
SCL
SP
START
CONDITION
SDA
SCL
DATA LINE STABLE;
DATA VALID
START
CONDITION
SCL
SDA BY
TRANSMITTER
SDA BY
RECEIVER
S
CHANGE OF DATA
ALLOWED
12 89
CLOCK PULSE
FOR ACKNOWLEDGE
STOP
CONDITION
SDA
MSB
SCL
1
LSB
ACK00A6 0 0A2 R/W
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