G786 Datasheet, PDF (1/1 Pages) Global Mixed-mode Technology Inc – ±1C Remote and Local Temperature Sensor with SMBus Serial Interface

Global Mixed-mode Technology Inc.
G786
±1°C Remote and Local Temperature Sensor with
SMBus Serial Interface
Features
„ Two Channels: Measures Both Remote and
Local Temperatures
„ No Calibration Required
„ Built-in Noise-Buster for Remote Sensor
„ SMBus 2-Wire Serial Interface
„ Programmable Under/Overtemperature Alarms
„ Supports SMBus Alert Response
„ Accuracy:
±1°C (+60°C to +100°C, remote)
±3°C (+60°C to + 100°C, local)
„ 320µA (typ) Average Supply Current During
Conversion
„ +3V to +5.5V Supply Range
„ Small 8-Lead SOP and MSOP Package
„ Remote Temperature Measurment up to 160°C
by using offset shifting method (see “Measure
Remote Temperature Higher Than 127°C” sec-
tion)
Applications
Desktop and Notebook
Computers
Smart Battery Packs
LAN Servers
Industrial Controllers
Central Office
Telecom Equipment
Test and Measurement
Multi-Chip Modules
Ordering Information
ORDER
NUMBER
G786P11U
G786P81U
G786-1P81U
Note:P1:SOP-8 P8:MSOP-8
1: Bonding Code
U: Tape & Reel
Pin Configuration
MARKING
G786
G786
G786-1
G786/G786-1
VCC 1
8 SMBCLK
DXP 2
7 SMBDATA
*DXN 3
6 ALERT
THERM 4
5 GND
SOP-8/MSOP-8
*: DXN : DXN is internally connected to GND.
General Description
The G786 is a precise digital thermometer that reports
the temperature of both a remote sensor and its own
package. The remote sensor is a diode-connected tran-
sistor typically a low-cost, easily mounted 2N3904 NPN
type that replace conventional thermistors or thermo-
couples. Remote accuracy is ±1°C with no calibration
needed. It also has a build-in noise filtering function in
remote sensor measuring the diode temperature. The
remote channel can also measure the die temperature
of other ICs, such as microprocessors, that contain an
on-chip, diode-connected transistor.
The 2-wire serial interface accepts standard System
Management Bus (SMBus) Write Byte, Read Byte,
Send Byte, and Receive Byte commands to program
the alarm thresholds and to read temperature data.
The data format is 11bits plus sign, with each bit cor-
responding to 0.125°C, in two’s-complement format.
Measurements can be done automatically and
autonomously, with the conversion rate programmed
by the user or programmed to operate in a single-shot
mode. The adjustable rate allows the user to control
the supply current drain.
The G786 and G786-1 have the same functions but
different SMBus slave addresses. This allows for one
of each to be on the bus at the same time.
The G786 is available in a small, 8-pin SOP and
MSOP surface-mount package.
TEMP.
RANGE
-55°C to +125°C
-55°C to +125°C
-55°C to +125°C
PACKAGE
(Green)
SOP-8
MSOP-8
MSOP-8
Typical Application Circuit
0.1µF
3V TO 5.5V
2N3904
VCC
DXP
SMBCLK
SMBDATA
DXN
2200pF
ALERT
THERM
GND
10kΩ EACH
CLOCK
DATA
INTERRUPT TO µC
Ver: 0.3
Apr 29, 2009
TEL: [phone]
http://www.gmt.com.tw
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