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BU9817FV
Multimedia ICs
4-channel temperature sensor IC for PCs with I2C BUS interface
BU9817FV
The BU9817FV is a 4-channel, 8-bit, A / D converter / overvoltage detector that is perfect for temperature sensors with built-in I2C BUS interfaces. The host can access the BU9817FV anytime for the voltage data.
!Applications Notebook computers, desktop computers, household electric appliances
!Features 1) By attaching a thermistor, a maximum four-channel temperature sensor is possible. 2) Can set comparison voltages independently. 3) Built-in I2C BUS interface. 4) Detection level and operating mode settings are programmable.
5) Extremely low operating current perfect for portable equipment. 6) Operating voltage of VDD = 3V to 5.5V.
!Absolute maximum ratings (Ta = 25°C)
Parameter Power supply voltage Power dissipation Operating temperature Storage temperature Voltage applied to pins Symbol VDD Pd Topr Tstg VIN Limits 7.0 350 – 15 ~ + 75 – 55 ~ +125 GND – 0.5 ~ VDD + 0.5 Unit V mW ˚C ˚C V
* Reduced by 3.5mW for each increase in Ta of 1˚C over 25˚C.
!Recommended operating conditions (Ta = 25°C)
Parameter Operating power supply voltage Symbol VDD Min. 3.0 Typ. — Max. 5.5 Unit V
Note) I2C BUS is a registered trademark philips.
BU9817FV
Multimedia ICs
!Block diagram
SDA
1 I2C BUS Interface
14
VDD
Vdl Register SCL 2
Pointer Register
Configuration Register 13 STOPB
Vul Register
Reset & Shutdown
OD1
3
Reset Voltage Hysteresis Comparator
Reset Shutdown ADV Register
12
AD1
OD2
4
Reset Voltage Hysteresis Comparator
11 ADV Register
AD2
Sel
8bit A/D
Sel
OD3
5
Reset Voltage Hysteresis Comparator
10 ADV Register
AD3
OD4
6
Reset Voltage Hysteresis Comparator
9
AD4
ADV Register
GND
7
8
CLK
BU9817FV
Multimedia ICs
!Pin descriptions
Pin No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Pin name SDA SCL OD1 OD2 OD3 OD4 GND CLK AD4 AD3 AD2 AD1 STOPB VDD I2C BUS Serial Data Line Function
I2C BUS Serial Clock Input 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
1
SDA
I2C BUS serial data input / output. When only input address accords slave address (BU9817FV's), register data is inputted or outputted.
2
SCL
I2C BUS serial clock input.
3 4 5 6
OD1 OD2 OD3 OD4
Open-drain output corresponds to AD1 to AD4 input. Connect this pin a pull-up resister. The pull-up resister should be above VDD / 4mA (Ω).
7
GND
Ground terminal.
8
CLK
Clock input for ADC block. Input clock is 32.768kHz. AD converter and voltage hysteresis comparator use this clock to operate.
BU9817FV
Multimedia ICs
!Input / output equivalent circuits
Pin. No Pin name Input / output circuits Function
9 10 11 12
AD1 AD2 AD3 AD4
AD input. Each channel is converted in order. (AD1, AD2, AD3, AD4, AD1,AD2...)
13
STOPB
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.
14
VDD
Power supply. Supply voltage 3.0V to 5.5V.
BU9817FV
Multimedia ICs
!Electrical characteristics (unless otherwise noted, VDD = 5.0V, Ta = 25°C)
Parameter Circuit current (normal) Symbol ICC Min. 0.2 Typ. 0.75 Max. 2.0 Unit mA Conditions SDA, SCL = “H” CLK = 32.768kHz SDA, SCL = “H” CLK = 32.768kHz Mode setting or STOPB = Low — — — — — loL = 4.0mA loL = 6.0mA CL = 400pF loL = 6.0mA —
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〉 VDD
ICC.sd
— VDD × 0.7 – 0.5 — – 1.0 — 0.0 0.0 — 10
1.0
2.0
µA V V µA µA pF V V ns µs
ViH ViL IiH IiL Ci VoLod VoLsda tfsda pwstopb
VDD 0.0 0.0 0.0 — 0.2 0.2 — —
VDD + 0.5 VDD × 0.3 1.0 — 10 0.6 0.6 250 —
GND
0.3VDD Minimum pulse width
〈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 8 — — 305 — — 2 1 — VDD bits LSB LSB µs V 2 points connected fCLK = 32.768kHz — — —
BU9817FV
Multimedia ICs
!Measurement circuit
820Ω
820Ω
820Ω I2C BUS Controller
A
2
13
820Ω
3 1.2kΩ
12
4 1.2kΩ
11
5 1.2kΩ
10
6 1.2kΩ
9
32.768kHz
7
8
A
Fig.1
N
N
N
N
A
A
A
1
V V V V V V
14
BU9817FV
Multimedia ICs
!Circuit operation Explanation of operating mode
Operating mode Normal mode Interval High mode Interval Low mode Shutdown mode Reset mode Configura.