ASM809 Datasheet, PDF (1/10 Pages) Alliance Semiconductor Corporation – 3 Pin Microcontroller Power Supply Supervisor

October 2003
rev 1.0
ASM809, ASM810
3 Pin Microcontroller Power Supply Supervisor
General Description
The ASM809/ASM810 are cost effective 3.0V, 3.3V and 5.0V
power supply supervisor circuits optimized for low-power
microprocessor (µP), microcontroller (µC) and digital systems.
They provide a reset output during power-up, power-down and
brown-out conditions. They provide excellent reliability by
eliminating external components and adjustments. The
ASM809/810 are improved drop-in replacements for the Maxim
MAX809/810 and feature 60% lower supply current.
A reset signal is issued if the power supply voltage drops below
a preset reset threshold and is asserted for at least 140ms after
the supply has risen above the reset threshold. The ASM809
has an active-low RESET output that is guaranteed to be in the
correct logic state for V_CC down to 1.1V. The ASM810 has an
active-high RESET output. The reset comparator is designed to
ignore fast transients on V_CC.
Low supply current makes the ASM809/ASM810 ideal for use
in portable and battery operated equipment. The
ASM809/ASM810 are available in a compact, industry standard
3-pin SOT23 package.
Six voltage thresholds are available to support 3V to 5V
systems:
RESET THRESHOLD
Suffix
L
M
J
T
S
R
Voltage
4.63
4.38
4.00
3.08
2.93
2.63
Features:
• Monitor 5V, 3.3V and 3V supplies
• 140ms min. reset pulse width
• Active-low reset valid with 1.1V supply (ASM809)
• Small 3-pin SOT-23 package
• No external components
• Specified over full temperature range - -40°C to 105°C
Applications
• Embedded controllers
• Portable/Battery operated systems
• Intelligent instruments
• Wireless communication systems
• PDAs and handheld equipment
• Computers
Typical Operating Circuit
V_CC
V_CC
RESET
(RESET)
GND
V_CC
µP
RESET (RESET)
Input
GND
Alliance Semiconductor
2575 Augustine Drive . Santa Clara, CA 95054 . Tel: [phone] . Fax: [phone] . www.alsc.com
Notice: The information in this document is subject to change without notice