AMC6821 Datasheet, PDF (5/54 Pages) Burr-Brown (TI) – Analog Monitor and Control Circuit

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AMC6821
DEVICE INFORMATION
SBAS386C – MAY 2006 – REVISED JULY 2007
SSOP-16
(body size: 5mm x 4mm)
PWM-OUT 1
TACH 2
OVR 3
NC 4
GND 5
V_DD 6
THERM 7
FAN-FAULT 8
AMC6821
16 SCLK
15 SDA
14 SMBALERT
13 A0
12 A1
11 PWM-MODE
10 IN+
9 IN-
NAME
PWM-OUT
TACH
OVR
NC
GND
V_DD
THERM
FAN-FAULT
IN–
IN+
PWM-MODE
A1
A0
SMBALERT
SDA
SCLK
PIN NO.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Table 1. TERMINAL FUNCTIONS
DESCRIPTION
Digital output, open-drain. PWM output to control fan speed.
Digital input. Fan tachometer input to measure the fan speed.
Digital output, open-drain, active low. Goes low when temperature reaches the critical shutdown
threshold or remote temperature sensor failed. (See the Interrupt section for details.)
Not connected. Reserved for manufacturer's testing.
System ground
Power supply, +3 to +5V
Digital input/output (open-drain). As an output, an active low output indicates the temperature over the
THERM temperature limit. As an input, the pin provides an external fan control. When the pin is pulled
low by external signal, the THERM-IN bit is set, and the fan is set to full-speed.
Digital open-drain output. Goes low when a fan failure is detected.
Negative analog differential input. Connected to cathode of external temperature-sensing diode.
Positive analog differential input. Connected to anode of external temperature-sensing diode
Pentium-IV™ substrate transistor or general-purpose 2N3904 type transistor.
PWM mode selection. When tied low (GND), the high PWM frequency range (1kHz to 40kHz) is
selected. When tied to V_DD or floated, the low PWM frequency range (10Hz to 94Hz) is selected.
Checked only on power-up or reset.
Device slave address selection pin (see the SMB Interface section for details). Checked only on
power-up or reset.
Device slave address selection pin (see the SMB Interface section for details). Checked only on
power-up or reset.
Digital output, open-drain, SMBALERT, active low. Requires a pull-up resistor (2.2kΩ typical).
Bi-directional digital I/O pin, SMBus data, open-drain. Requires a pull-up resistor (2.2kΩ typical).
Digital input, SMBus clock. Requires a pull-up resistor (2.2kΩ typical).
Copyright © 2006–2007, Texas Instruments Incorporated
Product Folder Link(s): AMC6821
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