Global Mixed-mode Technology Inc.
G690/G691
Microprocessor Reset IC
Features
General Description
ꢀPrecision Monitoring of +3V, +3.3V, and +5V
Power-Supply Voltages
The G690/G691 are microprocessor (µP) supervisory
circuits used to monitor the power supplies in µP and
digital systems. They provide excellent circuit reliability
and low cost by eliminating external components and
adjustments when used with +5V, +3.3V, +3.0V- pow-
ered circuits.
ꢀFully Specified Over Temperature
ꢀAvailable in Three Output Configurations
Push-Pull RESET Output (G690L)
Push-Pull RESET Output (G690H)
Open-Drain RESET Output (G691L)
ꢀ140ms min Power-On Reset Pulse Width
ꢀ10µA Supply Current
These circuits perform a single function: they assert a
reset signal whenever the VCC supply voltage declines
below a preset threshold, keeping it asserted for at
least 140ms after VCC has risen above the reset
threshold. Reset thresholds suitable for operation with
a variety of supply voltages are available.
ꢀGuaranteed Reset Valid to VCC = +1V
ꢀPower Supply Transient Immunity
ꢀNo External Components
ꢀ3-Pin SOT89, SOT23 and SC70 Packages
The G691L has an open-drain output stage, while the
G690 have push-pull outputs. The G691L’s open-drain
RESET output requires a pull-up resistor that can be
connected to a voltage higher than VCC. The G690L
have an active-low RESET output, while the G690H
has an active-high RESET output. The reset com-
parator is designed to ignore fast transients on VCC,
and the outputs are guaranteed to be in the correct
logic state for VCC down to 1V.
Applications
ꢀComputers
ꢀControllers
ꢀIntelligent Instruments
ꢀCritical µP and µC Power Monitoring
ꢀPortable / Battery-Powered Equipment
ꢀAutomotive
Low supply current makes the G690/G691 ideal for
use in portable equipment. The G690/G691 are avail-
able in 3-pin SOT89 or SOT23 or SC70 packages.
Pin Configuration
Typical Application
VCC
3
VCC
VCC
*
RPULL-UP
G690/G691
µP
INPUT
RESET
RESET
(RESET)
GND
GND
1
2
3
2
1
SOT 89
SOT23/SC70
*G691 ONLY
TEL: 886-3-5788833
http://www.gmt.com.tw
Ver: 1.3
Oct 31, 2002
1
GMT [ GLOBAL MIXED-MODE TECHNOLOGY INC ]
