ASC7512 ETC2 [List of Unclassifed Manufacturers], ASC7512 Datasheet - Page 2

• Manufacturer Part Number: ASC7512
• Description: DIGITAL TEMPERATURE SENSOR WITH INTEGRATED FAN CONTROL
• Manufacturer: ETC2 [List of Unclassifed Manufacturers]

Block Diagram
Pin Descriptions
© Andigilog, Inc. 2006
PWM
TACH /
ALERT
D+
D-
SMBDAT
SMBCLK
V
GND
D+
D-
TACH /
PWM
ALERT
DD
Symbol
Internal
Sensor
MUX
Pin
Pin
5
2
4
7
8
1
3
6
ditioning
Fan PWM Control Register
Analog
Tach Signal
Signal
Conditioner
Diode
Con-
Mux
Digital I/O
(Open-Drain)
Digital Input
POWER
GROUND
Remote Thermal Diode
Positive Input
Remote Thermal Diode
Negative Input
Digital Input / Digital
Open-Drain Output
Digital Open-Drain
Output
&
Speed
Fan
Type
Figure 1 Block Diagram
ADC
Reference
Bandgap
ID Registers
Address
Pointer
www.andigilog.com
Digital
Filter
- 2 -
System Management Bus Data. Open-drain output. 5V
tolerant, SMBus 2.0 compliant.
System Management Bus Clock. Tied to Open-drain output.
5V tolerant, SMBus 2.0 compliant.
+3.3V pin. Can be powered by +3.3V Standby power if
monitoring in low power states is required. This pin should
be bypassed with a 0.1μF capacitor in parallel with 100pF
Ground for all analog and digital circuitry.
Positive input (current source) from the remote thermal
diode serves as the positive input into the A/D. Connected
to the anode of a CPU thermal diode or the base-collector of
a diode connected MMBT3904 NPN transistor.
Negative input (current sink) from the remote thermal diode
serves as the negative input into the A/D. Connected to
cathode of a CPU thermal diode or the emitter of a diode
connected MMBT3904 NPN transistor.
Input for monitoring tachometer output of fan (default) or
Fan speed control, Pulse Width Modulated.
ALERT output selectable by configuration register 09h, bit 5.
Name and Function/Connection
Fan T-min, T-range & T-Hyst
Fan Characteristic Registers
Fan Speed Configuration
Configuration Register
SMBus Interface
Fan Control Registers
Limit Comparators
Spike Smoothing
Status Registers
Limit Registers
August 2006 - 70A05003
aSC7512
SMBDAT
SMBCLK