IMP706P/R/S/T/J, IMP708R/S/T/J
P
OWER
M
ANAGEMENT
Key Features
3/3.3/4.0V µP Supervisor Circuits
– Low supply current
– Watchdog timer
– Brownout detection
The IMP706P/R/S/T/J and IMP708R/S/T/J CMOS supervisor circuits
monitor power-supply and battery voltage level, and µP/µC operation.
A reset is generated when the supply drops below 2.63V (IMP706P/R,
IMP708R), 2.93V (IMP706S, IMP708S), 3.08V (IMP706T, IMP708T) or 4.00
(IMP706J, IMP708J).
ꢀ
ꢀ
Lower power, pin compatible replacements for
Maxim MAX706P/R/S/T, MAX708R/S/T
– 30% lower supply current:140µA vs. 200µA
Precision power supply monitor
– 2.63V threshold (IMP706P/R, IMP708R)
– 2.93V threshold (IMP706S, IMP708S)
– 3.08V threshold (IMP706T, IMP708T)
– New 4.00V threshold (IMP706J, IMP708J)
Debounced manual reset input
Auxiliary voltage monitor comparator
– 1.25V threshold
– Battery monitor/auxiliary supply monitor
Watchdog timer (IMP706P/R/S/T/J)
– Watchdog can be disabled by floating WDI
200ms reset time delay
ꢀ
ꢀ
The family offers several functional options. Each device generates a
reset signal during power-up, power-down and during brownout
conditions.
ꢀ
In addition, the IMP706P/R/S/T/J feature a 1.6 second watchdog timer.
The watchdog timer output will trigger a reset if connected to MR.
Unlike competitive devices, floating the WDI input pin disables the
watchdog timer.
ꢀ
ꢀ
Three reset signal options
– Active HIGH: IMP706P
– Active LOW: IMP706R/S/T/J
– Active HIGH & LOW outputs: IMP708R/S/T/J
DIP, SO and MicroSO packages
Guaranteed RESET assertion to VCC = 1.1V
The IMP708R/S/T/J have both active-HIGH and active-LOW reset out-
puts but no watchdog function. The IMP706P has the same pin-out and
functions as the IMP706R but has an active-HIGH reset output.
ꢀ
ꢀ
A versatile power-fail circuit, useful in checking battery levels and
non-5V supplies, has a 1.25V threshold. All devices have a manual
reset input.
Applications
All devices are available in 8-pin DIP, SO and the compact MicroSO
packages. The MicroSO package requires 50% less PC board area than
the conventional SO package.
ꢀ Computers and controllers
ꢀ CTI applications
ꢀ Embedded controllers
ꢀ Battery operated systems
ꢀ Intelligent instruments
ꢀ Wireless communication systems
ꢀ PDAs and handheld equipment
Block Diagrams
Transition
Detector
Watchdog
Timer
WDI
WDO
RESET
RESET
VCC
20kΩ
VCC
Timebase
20kΩ
RESET
Generator
MR
MR
RESET
(RESET) IMP706P
RESET
Generator
+
+
VCC
VCC
+
–
+
–
2.63V (IMP706P/R)
2.93V (IMP706S)
3.08V (IMP706T)
4.00V (IMP706J)
2.63V (IMP708R)
2.93V (IMP708S)
3.08V (IMP708T)
4.00V (IMP708J)
+
PFI
+
–
PFI
PFO
PFO
–
1.25V
1.25V
IMP708R/S/T/J
IMP706P/R/S/T/J
706P_02.eps
706P_01.eps
GND
GND
©
1999 IMP, Inc.
408-432-9100/www.impweb.com
1
IMP [ IMP, INC ]
