EM MICROELECTRONIC - MARIN SA
EM6325
Reset Circuit with Manual Reset
Description
Features
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 VDD rises above VTH, 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
Manual reset function
200ms reset timeout period (1.6ms, 25ms, 1600ms on
request)
Ultra-low supply current of 2.9μA (VDD=3.3V)
Operating temperature range: -40°C to +125°C
±1.5% reset threshold accuracy
11 reset threshold voltages VTH: 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
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.
Active-high RESET push-pull
Immune to short negative VDD transients
Guaranteed Reset valid down to 0.9V
Threshold hysteresis: 2.1% of VTH
Typical Application
VDD
Very small SOT23-5L, SC70-5L and SC70-4L
VDD
*
VDD
Applications
RESET
RESET
Computers
MPU, DSP
RESET
EM6325
RESET
Servers and workstations
Modems
MR
GND
GND
GND
Wireless communication
Metering
* REXT for open-drain version only
Playstations
Block Diagram
PDA , Webpad
Automotive systems
VDD
Oscillator
Pin Configuration (top view)
+
RESET
RESET
Reset
Logic
VDD
RESET
1
2
3
5
GND
VDD
MR
Voltage
push-pull / open-drain
1
2
4
3
-
Reference
GND
RESET
(RESET)
RESET
4
Filter
MR
MR
push-pull
SOT23-5 / SC70-5
SC70-4
top view
GND
top view
Pin Description
Pin
Name
Function
SOT23-5L / SC70-5L SC70-4L
Active-low RESET output. RESET remains low for the reset timeout period and
1
2
RESET
GND
then goes high after all reset conditions are deasserted or after MR goes from low
to high
Ground
2
3
1
2
Active-high RESET output. RESET remains high for the reset timeout period and
RESET
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
4
5
3
4
MR
VDD
long as MR is low and for tPOR after MR returns high. MR can be driven with a
CMOS output or shorted to ground with a switch
Supply Voltage (5.5V max.)
1
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