G680/1

G680/G681
Global Mixed-mode Technology
Microprocessor Reset IC
Features
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General Description
±2.5% Voltage Threshold Accuracy
Independently Adjustable High- and LowVoltage Thresholds
The G680/G681 are microprocessor (µP) supervisory
circuits used to monitor the power supplies in µP and
digital systems. High- and Low- voltage thresholds can
be adjusted independently, allowing for wide hysteresis. Voltage detection thresholds are accurate to 2%.
Fully Specified Over Temperature
Available in Three Output Configurations
Push-Pull RESET Output (G680L)
Push-Pull RESET Output (G680H)
Open-Drain RESET Output (G681L)
140ms min Power-On Reset Pulse Width
4µA Supply Current
Power Supply Transient Immunity
SOT-23-5 Packages
These circuits perform a single function: they assert a
reset signal whenever the VCC supply voltage declines
below the low-voltage threshold, keeping it asserted
for at least 140ms after VCC has risen above the
high-voltage threshold.
The G681L has an open-drain output stage, while the
G680 have push-pull outputs. The G681L’s open-drain
RESET output requires a pull-up resistor that can be
connected to a voltage higher than VCC. The G680L
have an active-low RESET output, while the G680H
has an active-high RESET output. The reset comparator is designed to ignore fast transients on threshold input.
Applications
„ Computers
„ Controllers
„ Intelligent Instruments
„ Critical µP and µC Power Monitoring
„ Portable / Battery-Powered Equipment
„ Automotive
The IC’s power supply is separate from the detector
inputs, allowing the G680/G681 to be powered from a
down-stream supply. Low supply current (4µA, typical)
makes the G680/G681 ideal for use in portable
equipment. The G680/G681 are available in SOT
-23-5 packages.
Ordering Information
ORDER NUMBER
(Pb free/Green)
MARKING
OUTPUT TYPE
TEMP.
RANGE
PACKAGE
G680LT1Uf
680Ax
Push-pull RESET
-40°C ~ +105°C
SOT-23-5
G680HT1Uf
680Bx
Push-pull RESET
-40°C ~ +105°C
SOT-23-5
G681LT1Uf
681Ax
Open-Drain RESET
-40°C ~ +105°C
SOT-23-5
Note: T1: SOT-23-5
Pin Configuration
Typical Application Circuit
VCC
G680/G681
HTH
1
5
Vcc
RPULL-UP*
LTH
GND
LTH
2
G680/G681
4
3
VCC
VCC
HTH
RESET(RESET)
RESET
(RESET)
GND
µP
RESET
INPUT
GND
SOT-23-5
*G681 ONLY
() is for G680H
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 2.0
Nov 23, 2012
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