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EM6354 Datasheet, PDF (1/7 Pages) EM Microelectronic - MARIN SA – Reset Circuit with Adjustable Delay
EM MICROELECTRONIC-MARIN SA
EM6354
Reset Circuit with Adjustable Delay
Description
The EM6354 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. 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 going
fully active. This delay time, or reset timeout period, can be
adjusted using an external capacitor.
The output is guaranteed to be in the correct state for VDD
down to 0.8V. There are 11 reset threshold voltages starting
as low as 1.31V and up to 4.63V. The EM6354 features
three output types: active-low push-pull, active-low open-
drain and active-high push-pull.
Small SC70 and SOT23 packages as well as ultra-low
supply current of 2.9µA make the EM6354 an ideal choice
for portable and battery-operated devices.
Typical Application
VDD
VDD
RESET
EM6354
CD
GND
GND
* REXT for open-drain version only
*
VDD
RESET
MPU, DSP
GND
Pin Configuration (top view)
RESET
(RESET) 1
VDD 2
GND 3
5 CD
4 NC
SOT23-5L
RESET 1
(RESET)
VDD 2
4 GND
3 CD
SC70-4L (SC-82AB)
Features
! Adjustable reset timeout period using an external
capacitor
! 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
Active-high RESET push-pull
! Immune to short negative VDD transients
! Guaranteed Reset valid down to 0.8V
! Threshold hysteresis: 2.1% of VTH
! Very small SOT23-5L and SC70-4L (SC-82AB)
packages
Applications
! Home appliances
! Modems
! Routers, hubs and gateways
! WAN, LAN
! Handheld GPS
! Metering and Instrumentation
! TV sets
! Automotive systems
Block Diagram
VDD
Voltage
Reference
-
+
Delay
Circuit
RESET
(RESET)
GND
CD
Pin Description
Pin
SOT23-5L SC70-4L
1
1
2
2
3
4
4
-
5
3
Name
RESET
RESET
VDD
GND
N.C.
CD
Function
Active-low RESET output. RESET remains low for the reset timeout period after all reset
conditions are deasserted and then goes high.
Active-high RESET output. RESET remains high for the reset timeout period after all reset
conditions are deasserted and then goes low.
Supply Voltage (5.5V max.)
Ground
Not connected. Not internally connected
Connect a capacitor between CD and GND to set the timeout period
(CD min=1nF; C D max=10000nF). Reset Timeout Period in [ms] is equal to CD in [nF]
Copyright © 2006, EM Microelectronic-Marin SA
1
03/06 – rev.I
www.emmicroelectronic.com