ROHM BU9817FV Datasheet

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.