Datasheet BU9817FV Datasheet (ROHM)

BU9817FV

Multimedia ICs

4-channel temperature sensor IC for

2

PCs with I

BU9817FV

The BU9817FV is a 4-channel, 8-bit, A / D converter / overvoltage detector that is perfect for temperature sensors with

2

built-in I

!

Notebook computers, desktop computers, household
electric appliances

!

1) By attaching a thermistor, a maximum four-channel
temperature sensor is possible.

2) Can set comparison voltages independently.

3) Built-in I

4) Detection level and operating mode settings are pro­ grammable.

C BUS interfaces. The host can access the BU9817FV anytime for the voltage data.

Applications

Features

2

C BUS interface.

C BUS interface

5) Extremely low operating current perfect for portable
equipment.

6) Operating voltage of V

DD

= 3V to 5.5V.

Absolute maximum ratings

!!!!

Parameter Symbol Limits Unit
Power supply voltage
Power dissipation
Operating temperature
Storage temperature
Voltage applied to pins

* Reduced by 3.5mW for each increase in Ta of 1˚C over 25˚C.

Recommended operating conditions

!!!!

Parameter Symbol UnitMax.Typ.Min.

Operating power supply voltage

(Ta = 25°C)

V

DD

Pd
Topr
Tstg

V

IN

V

DD

7.0

350

– 15 ~ + 75

– 55 ~ +125

GND – 0.5 ~ V

DD

(Ta = 25°C)

3.0 5.5— V

+ 0.5

V

mW

˚C
˚C

V

Note) I2C BUS is a registered trademark philips.

Multimedia ICs

Block diagram

!!!!

BU9817FV

SDA

SCL

OD1

OD2

Sel

14 VDD

13 STOPB

12

AD1

11

AD2

1

I2C BUS Interface

Vul
Register

Pointer
Register

Vdl

2

3

4

Reset
Voltage

Hysteresis
Comparator

Reset
Voltage

Hysteresis
Comparator

Register

ADV
Register

ADV
Register

Configuration
Register

Reset & Shutdown

Sel

Reset

Shutdown

8bit

A / D

OD3

OD4

GND

AD3

5

6

7

Reset
Voltage

Hysteresis
Comparator

Reset
Voltage

Hysteresis
Comparator

ADV
Register

ADV
Register

10

AD4

9

CLK

8

Multimedia ICs

Pin descriptions

!!!!

Pin No. Pin name Function

10
11
12
13
14

1
2
3
4
5
6
7
8
9

SDA
SCL
OD1
OD2
OD3
OD4
GND
CLK
AD4
AD3
AD2
AD1

STOPB

DD

V

I2C BUS Serial Data Line

2

C BUS Serial Clock Input

I
Open Drain Output 1
Open Drain Output 2
Open Drain Output 3
Open Drain Output 4
Ground
Clock for Logic Input
Analog-to-Digtal Converter Input 4
Analog-to-Digtal Converter Input 3
Analog-to-Digtal Converter Input 2
Analog-to-Digtal Converter Input 1
Reset & Power save mode set
Supply Voltage 3.0V to 5.5V

BU9817FV

Multimedia ICs

Input / output equivalent circuits

!!!!

Pin. No Pin name Input / output circuits Function

2

I

C BUS serial data input / output.

1

2

SDA

SCL

When only input address accords slave
address (BU9817FV's), register data is
inputted or outputted.

2

I

C BUS serial clock input.

BU9817FV

3
4
5
6

7

8

OD1
OD2
OD3
OD4

GND

CLK

Open-drain output corresponds to AD1 to
AD4 input.
Connect this pin a pull-up resister.
The pull-up resister should be above V
4mA (Ω).

Ground terminal.

Clock input for ADC block.
Input clock is 32.768kHz.
AD converter and voltage hysteresis
comparator use this clock to operate.

DD

/

Multimedia ICs

Input / output equivalent circuits

!!!!

Pin. No Pin name Input / output circuits Function

BU9817FV

10
11
12

13

14

9

AD1
AD2
AD3
AD4

STOPB

V

DD

AD input.
Each channel is converted in order.
(AD1, AD2, AD3, AD4, AD1,AD2...)

Reset and power save mode setting.
High: Operation mode

Operation follows the setting of
configuration register.

Low : Reset & Power save mode

Reset the all internal circuit and stop
the ADC operation.
Go into power save mode.

∗

Be sure to set STOPB pin low for initial
reset of the internal circuit, when the
BU9816FV is power up.

Power supply.
Supply voltage 3.0V to 5.5V.

Multimedia ICs

Electrical characteristics

!

BU9817FV

(unless otherwise noted, VDD = 5.0V, Ta = 25°C)

Parameter

Circuit current (normal)

Circuit current
(shutdown / reset / STOPB)

Input high level voltage
Input low level voltage
Input high level current
Input low level current
Input capacity

Open drain output
low level voltage

SDA
output low level voltage

SDA
output fall time

STOPB
minimum pulse width

〈STOPB minimum pulse width〉

V

DD

GND

Minimum pulse width

Symbol Min. Typ. Max. Unit Conditions

I

CC

0.2

0.75

2.0

mA

SDA, SCL = “H”
CLK = 32.768kHz

SDA, SCL = “H”

ICC.sd

—

1.0

2.0

CLK = 32.768kHz

µA

Mode setting or
STOPB = Low

—

V

—

V

—

µA

—

µA

—

pF

V

loL = 4.0mA

loL = 6.0mA

V

CL = 400pF

ns

loL = 6.0mA

µs

—

0.3V

iH

V

V

iL

I

iH

I

iL

Ci

VoLod

VoLsda

tfsda

pwstopb

DD

DD

V

– 0.5

—

– 1.0

—

0.0

0.0

—

10

× 0.7

V

0.0

0.0

0.0

—

0.2

0.2

—

—

DD

DD

+ 0.5

V
V

DD

× 0.3

1.0

—

10

0.6

0.6

250

—

〈A / D〉
AD resolution
Non-linearity error
Differential non-linearity error
1-channel conversion time
Input range

RES

Nle

Ndle

Tc

Ai

—
– 2
– 1

—

GND

—
—

305

—

8

—

—

V

bits

2

LSB

1

DD

LSB

µs

V

2 points connected
fCLK = 32.768kHz

—
—

—

Multimedia ICs

Measurement circuit

!

I2C BUS
Controller

BU9817FV

A

1

V

820Ω

V

820Ω

820Ω

A

2

820Ω

14

13

AA

V

1.2kΩ

V

1.2kΩ

V

1.2kΩ

V

1.2kΩ

3

4

5

6

7

12

11

10

9

8

NNNN

32.768kHz

A

Fig.1

Multimedia ICs

Circuit operation

!

Explanation of operating mode

Operating mode

Normal mode

Interval High mode

Interval Low mode

Shutdown mode

Configuration

register settings

00000

00110

00100

00000

∗∗

∗∗

∗∗

∗∗

0b

0b

0b

1b

ADC operation

conversion interval

1.221ms

1 second intervals

4 second intervals

Stopped

Open drain

operation timing
10th clock after

A / D conversion

10th clock after

A / D conversion

10th clock after

A / D conversion

Hold status

Register status

Normal operation

Normal operation

Normal operation

Hold data

BU9817FV

Current

consumption (typ.)

0.75mA

Note: average
less than 3µA

Note: average
less than 2µA

Less than 1µA

Reset mode

The asterisk can be either 0 or 1.

Conversion time is for fCLK = 32.768kHz.

∗

These mode setting bits (bit 0 and bits 3 to 5) are common for each channel, the last setting of bits (bit0 and bits3 to 5) is

∗

effective for all channels. Furthermore, bits 1 and 2 are independent and can be set for each channel.

Note: These parameters are reference values derived through calculations and are not guaranteed characteristic values.

∗

00

∗∗1∗∗∗

b

Stopped

Reset fixed at high

Data reset

Less than 1µA

Explanation of ADC / open drain operation

(Normal mode)

Tad = 1.221ms, 40 clock

10 clock

ADC operation

(Interval mode)

ADC operation

4ch 1ch 2ch 3ch 4ch 1ch 2ch 3ch 4ch 1ch
OD1
OD2

OD3
OD4

Tin = 1s, 4s

Tc = 1.831ms, 60 clock

10 clock 10 clock 10 clock

1ch 2ch 3ch 1ch 2ch 3ch4ch 1ch
OD1
OD2

OD3
OD4

BU9817FV

Multimedia ICs

Circuit operation

!

Explanation of I

• Slave address
1001111R / W

MSB LSB

• Conforms to I

SCL clock frequency
Start condition hold time
Start condition setup time
Data setup time
Data hold time
Stop condition setup time

(Start conditions)

2

C BUS interface

2

C BUS standards

Parameter Symbol Min. Max. Unit

0

f SCL
t HD: STA
t SU: STA
t SU: DAT
t HD: DAT
t SU: STO

0.6

0.6

100

0.6

400

—
—
—

0

0.9

—

kHz

µs
µs

ns

µs
µs

(Data conditions)

(Stop conditions)

SCL

SDA

SCL

SDA

SCL

SDA

t SU: STA

t SU: DAT t HD: DAT

t HD: STA

t SU: STO

Multimedia ICs

Circuit operation

!

OD output voltage response diagram

(Example: open-drain output is set active low)

Vul

Vdl

OD Output

(Comparator Mode)

BU9817FV

AD pin voltage waveform

OD Output

(Interrupt Mode)

∗∗∗

Read Read Read

Time

* Note: Resetting OD output under interrupt mode occurs at only shutdown mode or reset mode or STOPB or when data
read generated from host. Except for these cases, OD output is kept setting.

Multimedia ICs

Circuit operation

!

Register structure

SDA
SCL

I2C BUS
Interface

Pointer
Register

(Register select)

BU9817FV

1ch Configuration Register
1ch Vdl Register
1ch Vul Register
1ch ADV Register

2ch Configuration Register
2ch Vdl Register
2ch Vul Register
2ch ADV Register

3ch Configuration Register
3ch Vdl Register
3ch Vul Register
3ch ADV Register

I2C Bus data structure
(1) Write Mode

S Address

(2) Read Mode

1) Pointer register set

S Address

2) Preset pointer register

S Address

—

AAPointer reg. Byte Write Data Byte A P

W

—

AAPointer reg. Byte

W

Sr Address ARPRead Data Byte

ARPRead Data Byte

—

A

4ch Configuration Register
4ch Vdl Register
4ch Vul Register
4ch ADV Register

—

A

S: Start condition
P: Stop condition
Sr: Restart condition
A: acknowledge

—

A: acknowledge bar

Multimedia ICs

Mode settings table 1 / 2
(1) Pointer register (selects which registers will be read from or written to)

BU9817FV

D7 D6

00D50

D4 to D7: These bits are used for test mode and must be kept zero for normal operation.

Channel Select

D3 D2 Channel

0
0
1
1

Register Select

D1 D0 Register

0
0
1
1

D4

0

Channel 1

0

Channel 2

1

Channel 3

0

Channel 4

1

ADV Register (Read only) (Power on Reset default)

0

Configuration Register (Read / Write)

1

Vdl Register (Read / Write)

0

Vul Register (Read / Write)

1

D3

Channel Select

D2 D1

Register Select

D0

(2) ADV Register (Read only)

Channel D7 D6 D5 D4 D3 D2 D1 D0
1 ch
2 ch
3 ch
4 ch

D0 to D7: Voltage data
The defaults for the power-on-reset and reset modes are 1 for all bits.

MSB
MSB
MSB
MSB

bit6
bit6
bit6
bit6

bit5
bit5
bit5
bit5

bit4
bit4
bit4
bit4

bit3
bit3
bit3
bit3

bit2
bit2
bit2
bit2

bit1
bit1
bit1
bit1

LSB
LSB
LSB
LSB

(3) Configuration Register (Read / Write)

Channel D7 D6 D5 D4 D3 D2 D1 D0

1 ch

2 ch

3 ch

4 ch

The defaults for the power-on-reset and reset modes are 0 for all bits.

0

0

0

0

Interval

0

0

Mode

0

0

Interval

Speed

Reset Shutdown

Opendrain

Polarity

Opendrain

Polarity

Opendrain

Polarity

Opendrain

Polarity

Comp. / Int.

Comp. / Int.

Comp. / Int.

Comp. / Int.

BU9817FV

Multimedia ICs

Mode settings table 2 / 2

D0 : Shutdown
“0” - Operation mode.
“1” - The BU9817FV stops A / D operation and goes into low power shutdown mode.
D0 bit of each channel is common bit.
D1 : Comparator / Interrupt mode
“0” - Comparator mode.
“1” - Interrupt mode.
D2 : Open Drain Polarity
“0” - active low.
“1” - active high.
D3 : Reset
“0” - Operation mode.
“1” - Reset any bits except D3 bit of the configuration register, any registers, the A / D converter, and the
voltage hysteresis comparator.
D3 bit of each channel is common bit.
D4 : Interval Speed
Set the conversion cycle time of the 8bit A / D and the voltage hysteresis comparator when D5 bit (Interval
Mode) is “1”.
“0” - conversion cycle time is 4s.
“1” - conversion cycle time is 1s.
D4 bit of each channel is common bit.
D5 : Interval Mode
“0” - normal mode.
“1” - Interval mode.
D5 bit of each channel is common bit.

(4) Vul and Vdl Register (Read / Write)

Channel D7 D6 D5 D4 D3 D2 D1 D0
1 ch
2 ch
3 ch
4 ch

D0 to D7: Voltage limit data of Vul and Vdl.
Default after power on reset and reset mode is Vul = 80h, Vdl = 66h.

MSB
MSB
MSB
MSB

bit6
bit6
bit6
bit6

bit5
bit5
bit5
bit5

bit4
bit4
bit4
bit4

bit3
bit3
bit3
bit3

bit2
bit2
bit2
bit2

bit1
bit1
bit1
bit1

LSB
LSB
LSB
LSB

Multimedia ICs

Application example

!!!!

BU9817FV

DD

V

From system
controller

OD1 Output

OD2 Output

OD3 Output

SDA

SCL

1

2

3

4

5

14

13

12

11

10

STOPB Input (From Reset IC)
Power on Reset

V

DD

RS

AD1 Input

DD

V

RS

AD2 Input

AD3 Input

Thermal Zone

RTH

Thermal Zone

RTH

RTH: NTC Thermistor

OD4 Output

6

78

9

AD4 Input

CLK Input (fCLK = 32.768kHz)

Fig.2

BU9817FV

Multimedia ICs

Explanation for external components

!!!!

(1) AD input pin (example when used as a temperature sensor)
To the AD input pin, input a voltage with divided resistance from a resistor and NTC thermistor. For the sensor to
measure the temperature, the NTC thermistor is used. The thermistor is a p-type semiconductor and as the temperature
increases, the resistance value becomes lower. In other words, the resistance temperature coefficient is negative,
and so the AD input pin voltage temperature characteristics are also negative.

Put nearby BU9817FV

V

CC

ADx

GND is required common and stability.

External dimensions

!!!!

5.0 ± 0.2

14

4.4 ± 0.2

6.4 ± 0.3

1

0.1

1.15 ± 0.1

0.65

BU9817FV

(Units : mm)

8

7

0.22 ± 0.1

NTC thermistor

Put nearby measured object

0.15 ± 0.1

0.3Min.

0.1

SSOP-B14