IMP705/6/7/8, 813L
P
OWER
M
ANAGEMENT
Low-Power µP Supervisor Circuits
– Watchdog timer
– Brownout detection
– Power supply monitor
The IMP705/706/707/708 and IMP813L CMOS supervisor circuits
monitor power-supply and battery voltage level, and µP/µC operation.
Compared to pin-compatible devices offered by Maxim Integrated
Products, IMP devices feature 60 percent lower maximum supply current.
Key Features
ꢀ Improved replacements for the Maxim
MAX705/6/7/8, MAX813L
– 140µA maximum supply current
– 60% improvement
Precision power supply monitor
– 4.65V threshold (IMP705/707/813L)
– 4.40V threshold (IMP706/8)
Debounced manual reset input
ꢀ
ꢀ
ꢀ
Voltage monitor
– 1.25V threshold
The family offers several functional options. Each device generates a
reset signal during power-up, power-down and during brownout
conditions. A reset is generated when the supply drops below
4.65V (IMP705/707/813L) or 4.40V (IMP706/708). For 3V power supply
applications, refer to the IMP705P/R/S/T data sheet. In addition, the
IMP705/706/813L feature a 1.6 second watchdog timer. The IMP707/708
have both active-HIGH and active-LOW reset outputs but no watchdog
function. The IMP813L has the same pin-out and functions as the IMP705
but has an active-HIGH reset output. A versatile power-fail circuit has a
1.25V threshold, useful in checking battery levels and non-5V supplies. All
devices have a manual reset (MR) input. The watchdog timer output will
trigger a reset if connected to MR.
– Battery monitor/Auxiliary supply monitor
Watchdog timer (IMP705/706/813L)
200ms reset pulse width
Active HIGH reset output (IMP707/708/813L)
MicroSO package
ꢀ
ꢀ
ꢀ
ꢀ
Applications
ꢀ Computers and embedded controllers
ꢀ Battery-operated systems
All devices are available in 8-pin DIP, SO and MicroSO packages.
ꢀ Intelligent instruments
ꢀ Wireless communication systems
ꢀ PDAs and handheld equipment
Block Diagrams
Transition
Detector
Watchdog
Timer
WDI
WDO
RESET
RESET
VCC
0.25mA
VCC
Timebase
0.25mA
RESET
Generator
MR
MR
RESET
(RESET)
(IMP813L)
RESET
Generator
+
VCC
+
VCC
+
–
+
–
4.65V (IMP705/813L)
4.40V (IMP706)
4.65V (IMP707)
4.40V (IMP708)
+
PFI
+
–
PFI
PFO
PFO
–
1.25V
IMP705
1.25V
IMP707
IMP708
IMP706
IMP813L
705_02.eps
705_01.eps
GND
GND
©
1999 IMP, Inc.
408-432-9100/www.impweb.com
1