IMP706P/R/S/T/J, IMP708R/S/T/J
P
OWER
M
ANAGEMENT
3/3.3/4.0V µP Supervisor Circuits
– Lo w suppl y cur r ent
– Watc hdog timer
– Br o wnout det ection
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).
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.
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.
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.
Key Features
N
Lower power, pin compatible replacements for
Maxim MAX706P/R/S/T, MAX708R/S/T
– 30% lower supply current:140µA vs. 200µA
N
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)
N
Debounced manual reset input
N
Auxiliary voltage monitor comparator
– 1.25V threshold
– Battery monitor/auxiliary supply monitor
N
Watchdog timer (IMP706P/R/S/T/J)
– Watchdog can be disabled by floating WDI
N
200ms reset time delay
N
Three reset signal options
– Active HIGH: IMP706P
– Active LOW: IMP706R/S/T/J
– Active HIGH & LOW outputs: IMP708R/S/T/J
N
DIP, SO and MicroSO packages
N
Guaranteed RESET assertion to V
CC
= 1.1V
Applications
N
N
N
N
N
N
N
Computers and controllers
CTI applications
Embedded controllers
Battery operated systems
Intelligent instruments
Wireless communication systems
PDAs and handheld equipment
Block Diagrams
WDI
V
CC
Timebase
20kΩ
Transition
Detector
Watchdog
Timer
WDO
V
CC
20kΩ
RESET
MR
V
CC
+
+
–
RESET
Generator
RESET
(RESET) IMP706P
MR
V
CC
+
+
–
2.63V (IMP708R)
2.93V (IMP708S)
3.08V (IMP708T)
4.00V (IMP708J)
RESET
Generator
RESET
PFI
2.63V (IMP706P/R)
2.93V (IMP706S)
3.08V (IMP706T)
4.00V (IMP706J)
1.25V
+
–
PFO
PFI
1.25V
+
PFO
–
IMP706P/R/S/T/J
GND
706P_01.eps
IMP708R/S/T/J
706P_02.eps
GND
©
1999 IMP, Inc.
408-432-9100/www.impweb.com
1
IMP706P/R/S/T/J, IMP708R/S/T/J
Pin Configuration
DIP/SO
MR
V
CC
GND
PFI
1
2
IMP708R/S/T/J
MicroSO
8
7
WDO
RESET
WDI
PFO
MR
V
CC
GND
PFI
1
2
IMP706R/S/T/J
8
7
6
5
RESET
RESET
NC
PFO
MR
V
CC
GND
PFI
1
2
IMP706P
8
7
6
5
WDO
RESET
WDI
PFO
(RESET) RESET
(IMP706P)
WDO
MR
V
CC
1
2
3
4
IMP706P
IMP706R/S/T/J
8
7
6
5
WDI
PFO
PFI
GND
RESET
RESET
MR
V
CC
1
2
3
4
IMP708R/S/T/J
8
7
6
5
NC
PFO
PFI
GND
3
4
3
4
6
5
3
4
706P_03.eps
Ordering Information
Part Number
IMP706PCPA
IMP706PCSA
IMP706PCUA
IMP706PEPA
IMP706PESA
IMP706RCPA
IMP706RCSA
IMP706RCUA
IMP706REPA
IMP706RESA
IMP706SCPA
IMP706SCSA
IMP706SCUA
IMP706SEPA
IMP706SESA
IMP706TCPA
IMP706TCSA
IMP706TCUA
IMP706TEPA
IMP706TESA
IMP706JCPA
IMP706JCSA
IMP706JCUA
IMP706JEPA
IMP706JESA
IMP708RCPA
IMP708RCSA
IMP708RCUA
IMP708REPA
IMP708RESA
IMP708SCPA
IMP708SCSA
IMP708SCUA
IMP708SEPA
IMP708SESA
IMP708TCPA
IMP708TCSA
IMP708TCUA
IMP708TEPA
IMP708TESA
IMP708JCPA
IMP708JCSA
IMP708JCUA
IMP708JEPA
IMP708JESA
Package
8-Plastic DIP
8-SO
8-MicroSO
8-Plastic DIP
8-SO
8-Plastic DIP
8-SO
8-MicroSO
8-Plastic DIP
8-SO
8-Plastic DIP
8-SO
8-MicroSO
8-Plastic DIP
8-SO
8-Plastic DIP
8-SO
8-MicroSO
8-Plastic DIP
8-SO
8-Plastic DIP
8-SO
8-MicroSO
8-Plastic DIP
8-SO
8-Plastic DIP
8-SO
8-MicroSO
8-Plastic DIP
8-SO
8-Plastic DIP
8-SO
8-MicroSO
8-Plastic DIP
8-SO
8-Plastic DIP
8-SO
8-MicroSO
8-Plastic DIP
8-SO
8-Plastic DIP
8-SO
8-MicroSO
8-Plastic DIP
8-SO
Operating
Temperature Range
0°C to +70°C
0°C to +70°C
0°C to +70°C
–40°C to +85°C
–40°C to +85°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
–40°C to +85°C
–40°C to +85°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
–40°C to +85°C
–40°C to +85°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
–40°C to +85°C
–40°C to +85°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
–40°C to +85°C
–40°C to +85°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
–40°C to +85°C
–40°C to +85°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
–40°C to +85°C
–40°C to +85°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
–40°C to +85°C
–40°C to +85°C
0°C to +70°C
0°C to +70°C
0°C to +70°C
–40°C to +85°C
–40°C to +85°C
Reset Threshold
2.63
2.63
2.63
2.63
2.63
2.63
2.63
2.63
2.63
2.63
2.93
2.93
2.93
2.93
2.93
3.08
3.08
3.08
3.08
3.08
4.00
4.00
4.00
4.00
4.00
2.63
2.63
2.63
2.63
2.63
2.93
2.93
2.93
2.93
2.93
3.08
3.08
3.08
3.08
3.08
4.00
4.00
4.00
4.00
4.00
Reset Polarity
HIGH
HIGH
HIGH
HIGH
HIGH
LOW
LOW
LOW
LOW
LOW
LOW
LOW
LOW
LOW
LOW
LOW
LOW
LOW
LOW
LOW
LOW
LOW
LOW
LOW
LOW
Dual: HIGH & LOW
Dual: HIGH & LOW
Dual: HIGH & LOW
Dual: HIGH & LOW
Dual: HIGH & LOW
Dual: HIGH & LOW
Dual: HIGH & LOW
Dual: HIGH & LOW
Dual: HIGH & LOW
Dual: HIGH & LOW
Dual: HIGH & LOW
Dual: HIGH & LOW
Dual: HIGH & LOW
Dual: HIGH & LOW
Dual: HIGH & LOW
Dual: HIGH & LOW
Dual: HIGH & LOW
Dual: HIGH & LOW
Dual: HIGH & LOW
Dual: HIGH & LOW
Watchdog Timer
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
©
1999 IMP, Inc.
2
408-432-9100/www.impweb.com
IMP706P/R/S/T/J, IMP708R/S/T/J
Absolute Maximum Ratings
Pin Terminal Voltage with Respect to Ground
V
CC
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3V to 6.0V
All other inputs . . . . . . . . . . . . . . . . . . . . . . . . –0.3V to (V
CC
+ 0.3V)
Input Current at V
CC
and GND . . . . . . . . . . 20mA
Output Current: All outputs . . . . . . . . . . . . . 20mA
Rate of Rise at V
CC
. . . . . . . . . . . . . . . . . . . . . 100V/µs
Plastic DIP Power Dissipation . . . . . . . . . . . 700mW
(Derate 9mW/°C above 70°C)
SO Power Dissipation . . . . . . . . . . . . . . . . . . 470mW
(Derate 5.9mW/°C above 70°C)
MicroSO Power Dissipation . . . . . . . . . . . . . 330mW
(Derate 4.1mW/°C above 70°C)
Operating Temperature Range
IMP706xE, IMP708xE . . . . . . . . . . . . . . . . . . –40°C to +85°C
IMP706xC, IMP708xC . . . . . . . . . . . . . . . . . . 0°C to +70°C
Storage Temperature Range . . . . . . . . . . . . . . –65°C to +160°C
Lead Temperature Soldering (10 sec) . . . . . . 300°C
These are stress ratings only and functional operation is not implied.
Exposure to absolute maximum ratings for prolonged time periods may
affect device reliability.
Electrical Characteristics
Unless otherwise noted, specifications are over the operating temperature range and V
CC
supply voltages are 2.7V to 5.5V (IMP706P,
IMP708R), 3.0V to 5.5V (IMP706/8S), 3.15V to 5.5V (IMP706/8T) and 4.1V to 5.5V (IMP706/8J).
Parameter
Operating Voltage
Range
Supply Current
V
CC
< 3.6V
Supply Current
V
CC
< 5.5V
RESET Threshold
Symbol
V
CC
I
CC
I
CC
V
RT
Conditions
IMP706xC, IMP708xC
IMP706xE, IMP708xE
IMP706xC, IMP706xE, MR = V
CC
, WDI Floating
IMP708xC, IMP708xE, MR = V
CC
, WDI Floating
IMP706xC, IMP706xE, MR = V
CC
, WDI Floating
IMP708xC, IMP708xE, MR = V
CC
, WDI Floating
P and R devices
S devices
T devices
J devices
Min
1.1
1.2
Typ
Max
5.5
5.5
Units
V
µA
µA
V
75
50
75
50
2.55
2.85
3.00
3.89
2.63
2.93
3.08
4.00
40
140
140
140
140
2.70
3.00
3.15
4.10
RESET Threshold
Hysteresis
RESET Pulse Width
t
RS
V
CC
= 3V (IMP706/8, P/R devices),
V
CC
= 3.3V (IMP706/8, S/T devices)
V
CC
= 4.4V (IMP706/8, J devices)
V
CC
= 5V
MR Pulse Width
t
MR
4.5V < V
CC
< 5.5V
3.6V < V
CC
< 4.5V (IMP706/8J devices)
V
RST (MAX)
< V
CC
< 3.6V (IMP706/8P/R/S/T devices)
MR to RESET Out Delay
t
MD
3.6V < V
CC
< 4.5V (IMP706/8J devices)
V
RST(MAX)
< V
CC
< 3.6V (IMP706/8P/R/S/T devices)
4.5V < V
CC
< 5.5V
MR Input Threshold
V
IH
V
IL
V
IH
V
IL
MR Pull-up Resistor
RESET Output Voltage
(All R/S/T/J devices)
R
P
V
OH
V
OL
V
OH
V
OL
V
OL
I
SOURCE
= 800
µ
A, 4.5V < V
CC
< 5.5V
I
SINK
= 3.2mA, 4.5V < V
CC
< 5.5V
I
SOURCE
= 500
µ
A, V
RST (MAX)
< V
CC
< 4.5V
I
SINK
= 1.2mA, V
RST (MAX)
< V
CC
< 4.5V
I
SINK
= 50
µ
A, V
CC
= 1.1V (IMP706xC, IMP708xC devices)
I
SINK
= 100
µ
A, V
CC
= 1.2V (IMP706xE, IMP708xE devices)
©
1999 IMP, Inc.
mV
280
ms
140
200
200
150
500
750
250
0.7V
CC
0.6
2.0
0.8
10
V
CC
–1.5V
0.4
0.8 V
CC
0.3
0.3
0.3
20
40
kΩ
V
V
ns
ns
V
RST (MAX)
< V
CC
< 4.5V
V
RST (MAX)
< V
CC
< 4.5V
4.5V < V
CC
< 5.5V
4.5V < V
CC
< 5.5V
408-432-9100/www.impweb.com
3
IMP706P/R/S/T/J, IMP708R/S/T/J
Electrical Characteristics
(cont.)
Unless otherwise noted, specifications are over the operating temperature range and V
CC
supply voltages are 2.7V to 5.5V (IMP706P,
IMP708R), 3.0V to 5.5V (IMP706/8S), 3.15V to 5.5V (IMP706/8T) and 4.1V to 5.5V (IMP706/8J).
Parameter
RESET Output Voltage
IMP706P
Symbol
V
OH
V
OL
V
OH
V
OL
Conditions
I
SOURCE
= 800
µ
A, 4.5V < V
CC
< 5.5V
I
SINK
= 3.2mA, 4.5V < V
CC
< 5.5V
I
SOURCE
= 500
µ
A, V
RST (MAX)
< V
CC
< 3.6V
I
SINK
= 1.2mA, V
RST (MAX)
< V
CC
< 3.6V
I
SOURCE
= 800
µ
A, 4.5V < V
CC
< 5.5V
I
SINK
= 3.2mA, 4.5V < V
CC
< 5.5V
I
SOURCE
= 500
µ
A, V
RST (MAX)
< V
CC
< 4.5V
I
SINK
= 1.2mA, V
RST (MAX)
< V
CC
< 4.5V
V
CC
= 3V (IMP706, P/R devices)
V
CC
= 3.3V (IMP706, S/T devices)
V
CC
= 4.4V (IMP706, J devices)
V
IL
= 0.4V, V
IH
= 0.8V
CC
, V
RST (MAX)
< V
CC
< 4.5V
V
IL
= 0.4V, V
IH
= 0.8V
CC
, 4.5V < V
CC
< 5.5V
V
CC
= 5V
V
RST (MAX)
< V
CC
< 4.5V
WDI = V
CC
, IMP706 Only
WDI = 0V, IMP706 Only
Min
V
CC
–1.5V
Typ
Max
0.4
Units
V
0.8V
CC
0.3
V
CC
–1.5V
0.4
0.8V
CC
0.3
1.0
1.6
2.25
s
V
RESET Output Voltage,
IMP708R/S/T/J
V
OH
V
OL
V
OH
V
OL
Watchdog Timeout Period
t
WD
WDI Pulse Width
WDI Pulse Width
WDI Input Threshold
t
WP
t
WP
V
IH
V
IL
V
IH
V
IL
100
50
3.5
0.8
0.7V
CC
0.6
50
–150
V
CC
–1.5V
0.4
0.8V
CC
0.3
1.2
–25
1.25
0.01
1.3
25
–50
150
ns
ns
V
WDI Input Current
WDI Input Current
WDO Output Voltage
V
OH
V
OL
V
OH
V
OL
PFI Input Threshold
PFI Input Current
PFO Output Voltage
V
OH
V
OL
V
OH
V
OL
µA
µA
V
I
SOURCE
= 800
µ
A, 4.5V < V
CC
< 5.5V
I
SINK
= 1.2mA, 4.5V < V
CC
< 5.5V
I
SOURCE
= 500
µ
A, V
RST (MAX)
< V
CC
< 4.5V
I
SINK
= 500
µ
A, V
RST (MAX)
< V
CC
< 4.5V
PFI falling. For P/R devices V
CC
= 3V. For S/T
devices V
CC
= 3.3V. For J devices V
CC
= 4.4V.
I
SOURCE
= 800
µ
A, 4.5V < V
CC
< 5.5V
I
SINK
= 3.2mA, 4.5V < V
CC
< 5.5V
I
SOURCE
= 500
µ
A, V
RS (MAX)
< V
CC
< 4.5V
I
SINK
= 1.2mA, V
RS (MAX)
< V
CC
< 4.5V
V
nA
V
V
CC
–1.5V
0.4
0.8V
CC
0.3
4
408-432-9100/www.impweb.com
©
1999 IMP, Inc.
IMP706P/R/S/T/J, IMP708R/S/T/J
Pin Descriptions
Pin Number
IMP706P
IMP706R/S/T/J IMP708R/S/T/J
DIP/SO MicroSO DIP/SO MicroSO DIP/SO MicroSO Name
1
3
1
3
1
3
MR
Function
Manual reset input. The active LOW input triggers
a reset pulse. It is pulled HIGH by a 20kΩ pull-up
resistor. It is compatible with TTL/CMOS signals
when V
CC
= 5V. It can be shorted to ground
through a mechanical switch. Leave floating or
connect to V
CC
if the function is not used.
Monitored power supply input.
Ground
Power-fail input voltage monitor. With PFI less than
1.25V, PFO goes LOW. Connect PFI to ground
when not used.
Power-fail output. The output is active LOW and
sinks current when PFI is less than 1.25V. If not
used, leave the pin unconnected.
Watchdog input. WDI controls the internal watchdog
timer. A HIGH or LOW signal for 1.6 sec at WDI
allows the internal timer to run-out, setting WDO low.
A rising or falling edge must occur at WDI within
1.6 seconds or WDO goes LOW. The watchdog
function is disabled by floating WDI. The internal
watchdog timer clears when: RESET is asserted;
WDI is three-stated; or WDI sees a rising or falling edge.
Not connected.
Active-LOW reset output. Pulses LOW for 200ms
when triggered, and stays LOW whenever V
CC
is
below the reset threshold. RESET remains LOW for
200ms after V
CC
rises above the RESET threshold
or MR goes from HIGH to LOW. A watchdog timeout
will not trigger RESET unless WDO is connected to MR.
Watchdog output. WDO goes LOW when the 1.6
second internal watchdog timer times-out and does
not go HIGH until a transition occurs at WDI. In
addition, when V
CC
falls below the reset threshold,
WDO goes LOW. Unlike RESET, WDO does not have
a minimum pulse width and as soon as V
CC
exceeds
the reset threshold, WDO becomes HIGH with no delay.
Active-HIGH reset output. RESET is the inverse of
RESET.
2
3
4
4
5
6
2
3
4
4
5
6
2
3
4
4
5
6
V
CC
GND
PFI
5
7
5
7
5
7
PFO
6
8
6
8
—
—
WDI
—
—
—
—
6
8
NC
—
—
7
1
7
1
RESET
8
2
8
2
—
—
WDO
7
1
—
—
8
2
RESET
Feature Summary
IMP706P IMP706R IMP706S IMP706T IMP706J IMP708R IMP708S IMP708T IMP708J
Power-fail detector
I
I
I
I
I
I
I
I
I
Brownout detection
I
I
I
I
I
I
I
I
I
Debounced manual RESET input
I
I
I
I
I
I
I
I
I
Power-up/down RESET
I
I
I
I
I
I
I
I
I
Watchdog timer
I
I
I
I
I
Active-HIGH RESET
I
Active-LOW RESET
I
I
I
I
Active-LOW and HIGH RESETs
I
I
I
I
RESET threshold
2.63V
2.63V
2.93V
3.08V
4.00V
2.63V
2.93V
3.08V
4.00V
©
1999 IMP, Inc.
408-432-9100/www.impweb.com
5
