EM6325 Datasheet, PDF (1/8 Pages) EM Microelectronic - MARIN SA – Reset Circuit with Manual Reset

EM MICROELECTRONIC - MARIN SA
EM6325
Reset Circuit with Manual Reset
Description
The EM6325 is an ultra-low current reset circuit available in a
large variety of configurations and very small packages for
maximum flexibility in all end-applications up to 125°C and
using power supplies between 1.5V and 5.5V.
This circuit monitors the supply voltage of any electronic
system, and generates the appropriate reset signal after a
fixed reset timeout period. The threshold defines the
minimum allowed voltage which guarantees the good
functionality of the system. When V_DD rises above V_TH, the
output remains active for an additional delay time. This
allows the system to stabilize before getting fully active.
This circuit features a Manual Reset: an input that asserts
reset when pulled low ( MR with internal pull-up).
Small SC70-4L, SC70-5L and SOT23-5L packages as well
as ultra-low supply current of 2.9μA make the EM6325 an
ideal choice for portable and battery-operated devices.
Typical Application
V_DD
V_DD
RESET
EM6325
RESET
MR
GND
GND
* R_EXT for open-drain version only
*
V_DD
RESET
MPU, DSP
RESET
GND
Block Diagram
V_DD
Oscillator
+
Voltage
Reference
-
Reset
Logic
RESET
RESET
MR
GND
Filter
Features
‰ Manual reset function
‰ 200ms reset timeout period (1.6ms, 25ms, 1600ms on
request)
‰ Ultra-low supply current of 2.9μA (V_DD=3.3V)
‰ Operating temperature range: -40°C to +125°C
‰ ±1.5% reset threshold accuracy
‰ 11 reset threshold voltages V_TH: 4.63V, 4.4V, 3.08V,
2.93V, 2.63V, 2.2V, 1.8V, 1.66V, 1.57V, 1.38V, 1.31V
‰ 3 reset output options:
Active-low RESET push-pull
Active-low RESET open-drain
Active-high RESET push-pull
‰ Immune to short negative V_DD transients
‰ Guaranteed Reset valid down to 0.9V
‰ Threshold hysteresis: 2.1% of V_TH
‰ Very small SOT23-5L, SC70-5L and SC70-4L
Applications
‰ Computers
‰ Servers and workstations
‰ Modems
‰ Wireless communication
‰ Metering
‰ Playstations
‰ PDA , Webpad
‰ Automotive systems
Pin Configuration (top view)
RESET 1
push-pull / open-drain
GND ²
5 ^VDD
RESET 3
push-pull
4 _MR
SOT23-5 / SC70-5
top view
GND 1
4 V_DD
RESET ₂
(RESET)
3 MR
SC70-4
top view
Pin Description
Pin
SOT23-5L / SC70-5L SC70-4L
Name
1
2
RESET
2
1
GND
3
2
RESET
4
3
MR
5
4
V_DD
Function
Active-low RESET output. RESET remains low for the reset timeout period and
then goes high after all reset conditions are deasserted or after MR goes from low
to high
Ground
Active-high RESET output. RESET remains high for the reset timeout period and
then goes low after all reset conditions are deasserted or after MR goes from low to
high
Manual Reset input with an internal pull-up 15kΩ resistor. Reset remains active as
long as MR is low and for t_POR after MR returns high. MR can be driven with a
CMOS output or shorted to ground with a switch
Supply Voltage (5.5V max.)
Copyright © 2005, EM Microelectronic-Marin SA
1
www.emmicroelectronic.com