G780 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.
G780
±1°C Remote and Local Temperature Sensor with
SMBus Serial Interface
Features
„ Two Channels: Measures Both Remote and
Local Temperatures
„ Measure Thermal Diode with a Transistor Model
„ 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
„ Measure Thermal Diode with Transistor Model
„ Support 45nm, 65nm and 90nm CPU thermal
diode
„ +3V to +5.5V Supply Range
„ Small 8-Lead SOP , MSOP and TDFN Package
„ Remote Temperature Measurment up to 160°C
by using offset shifting method (see “Measure
Remote Temperature Higher Than 127°C” sec-
tion)
General Description
The G780 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.
Applications
Desktop and Notebook
Computers
Smart Battery Packs
LAN Servers
Industrial Controllers
Central Office
Telecom Equipment
Test and Measurement
Multi-Chip Modules
The G780 is available in a small, 8-pin SOP, MSOP
and TDFN surface-mount package.
Ordering Information
ORDER
NUMBER
MARKING
G780P11U
G780
G780P81U
G780
G780RD1U
780
G780-1P11U
G780-1
G780-1P81U
G780-1
Note:P1:SOP-8 P8:MSOP-8 RD:TDFN3X3-8
1: Bonding Code
U: Tape & Reel
Pin Configuration
G780/G780-1
VCC 1
DXP 2
DXN 3
THERM 4
8 SMBCLK
VCC 1
7 SMBDATA _{DXP 2}
6 ALERT ^{DXN 3}
5 GND
THERM 4
G780
Thermal
Pad
8 SMBCLK
7 SMBDATA
6 ALERT
5 GND
SOP-8/MSOP-8
TDFN3X3-8
Note: Recommend connecting the Thermal Pad to the GND or let it keep floating.
TEMP.
RANGE
-55°C to +125°C
-55°C to +125°C
-55°C to +125°C
-55°C to +125°C
-55°C to +125°C
PACKAGE
(Pb free)
SOP-8
MSOP-8
TDFN3X3-8
SOP-8
MSOP-8
Typical Application Circuit
0.1µF
3V TO 5.5V
2N3904
VCC
DXP
SMBCLK
SMBDATA
2200pF
DXN
ALERT
THERM
GND
10kΩ EACH
CLOCK
DATA
INTERRUPT TO µC
Ver: 0.5
Oct 02 , 2008
TEL: [phone]
http://www.gmt.com.tw
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