1
www.fairchildsemi.com
FM803 3-Pin
C Supervisor Device
www.fairchildsemi.com
FM803 Rev. C.3
FM803
3-Pin
C Supervisor Device
General Description
The FM803 is a supervisory device designed to monitor power
supply or other system voltage. FM803 generates a reset pulse
whenever the voltage being monitored is out of tolerance. Once
asserted, the reset pulse is guaranteed to be valid for a minimum
of 140ms (256ms typical ). The reset output of FM803 is of active
low Open-Drain type and has an internal pull-up resistor.
Several threshold voltages are offered to accommodate 5.0V,
3.3V, 3.0V and 2.7V system voltages.
These devices are offered in space saving 3-pin SOT23 and SC70
packages.
Typical Operating Circuit
October 2002
Features
I Automatic reset generation on power-up
I Minimum 140 ms reset pulse
I Internal 5k pull-up resistor
I Other reset pulse choices available: 32 - 256 ms
I Operating temperature
-40
C to + 105C (SOT-23)
-40
C to +85C (SC70)
I Choice of Reset Thresholds: 4.63V, 4.38V, 4.00V, 3.08V,
2.93V, 2.63V
I SOT23-3 and SC70-3 Packages
2000 Fairchild Semiconductor International
Connection Diagram
GND
V
CC
/RESET
1
FM803
2
3
SC70-3 & SOT23-3 Packages
1
FM803
Controller
2
3
V
CC
GND
/RESET
2
www.fairchildsemi.com
FM803 3-Pin
C Supervisor Device
www.fairchildsemi.com
FM803 Rev. C.3
Absolute Maximum Ratings
Voltage on any terminal relative to GND
V
CC
-0.3V to +6.0V
/RESET
-0.3V to +6.0V
Input Current
20mA
Output Current: /RESET
20mA
Rate of Rise of V
CC
100V/
s
Continuous Power Dissipation (T
A
= +70
C)
SOT23-3 (derate 4mW/
C above +70C)
320mW
Operating Temperature Range
-40
C to +105C
Storage Temperature Range
-65
C to +150C
Lead Temperature (soldering, 10s)
+300
C
These are stress ratings only, and functional operation is not implied for these levels or beyond. Exposure to Absolute Maximum Rating
conditions for extended periods may affect device reliability.
Electrical Characteristics
SOT-23 Package (T
A
= 25
C unless otherwise noted)
V
CC
= full range, as noted under conditions. See Note 1.
Parameter
Symbol
Conditions
Min
Typ
Max
Units
(Note 2)
Operating Voltage
V
CC
T
A
= -40
C to +105C
1.1
5.5
V
Supply Current
I
CC
T
A
= -40
C to +105C, V
CC
< 5.5V
5
10
A
FM803J/L/M
T
A
= -40
C to +105C, V
CC
< 3.6V
3
6
FM803R/S/T
Reset Threshold
V
TH
FM803L
T
A
= -40
C to +105C
4.40
4.63
4.86
V
FM803M
T
A
= -40
C to +105C
4.18
4.38
4.52
FM803J
T
A
= -40
C to +105C
3.90
4.00
4.18
FM803T
T
A
= -40
C to +105C
2.97
3.08
3.19
FM803S
T
A
= -40
C to +105C
2.79
2.93
3.00
FM803R
T
A
= -40
C to +105C
2.49
2.63
2.70
Reset Threshold Tempco
30
ppm/
C
V
CC
to Reset Delay
V
CC
= V
TH
to (V
TH
- 100mV)
10
s
Reset Active Timout Period
T
A
= -40
C to +105C
140
256
560
ms
FM803 Output Low
V
OL
V
CC
= V
TH
(min), I
SINK
= 1.2mA,
0.3
V
FM803R/S/T
V
CC
= V
TH
(min), I
SINK
= 3.2mA,
0.4
FM803J/L/M
V
CC
= < 1.0V, I
SINK
= 50
A
0.3
Open-Drain Output Leakage
V
CC
> V
TH
(max), I
RESET
= 1
0.8V
CC
1
A
Current
Note 1: Testing in production is 25
C only. Limits over temperature are guaranteed by design.
Note 2: Typical values are at 25
C.
Note 3: Recommended minimum slew rate for the V
CC
rampup is 200mV/sec in the 0 to 2V range for the device to function properly.
3
www.fairchildsemi.com
FM803 3-Pin
C Supervisor Device
www.fairchildsemi.com
FM803 Rev. C.3
Absolute Maximum Ratings
Voltage on any terminal relative to GND
V
CC
-0.3V to +6.0V
/RESET
-0.3V to (V
CC
+ 0.3V)
Input Current
20mA
Output Current: /RESET
20mA
Rate of Rise of V
CC
100V/
s
Continuous Power Dissipation (T
A
= +70
C)
SC70-3
174mW
Operating Temperature Range
-40
C to +85C
Storage Temperature Range
-65
C to +150C
Lead Temperature (soldering, 10s)
+300
C
These are stress ratings only, and functional operation is not implied for these levels or beyond. Exposure to Absolute Maximum Rating
conditions for extended periods may affect device reliability.
Electrical Characteristics
SC70 Package (T
A
= 25
C unless otherwise noted)
V
CC
= full range, as noted under conditions. See Note 1.
Parameter
Symbol
Conditions
Min
Typ
Max
Units
(Note 2)
Operating Voltage
V
CC
T
A
= 0
C to +70C
1.4
5.5
V
T
A
= -40
C to +85C
1.6
5.5
Supply Current
I
CC
T
A
= -40
C to +85C, V
CC
< 5.5V
9
15
A
FM803J/L/M
T
A
= -40
C to +85C, V
CC
< 3.6V
6
10
FM803R/S/T
Reset Threshold
V
TH
FM803L
T
A
= -40
C to +85C
4.40
4.63
4.86
V
FM803M
T
A
= -40
C to +85C
4.18
4.38
4.52
FM803J
T
A
= -40
C to +85C
3.90
4.00
4.18
FM803T
T
A
= -40
C to +85C
2.97
3.08
3.19
FM803S
T
A
= -40
C to +85C
2.79
2.93
3.00
FM803R
T
A
= -40
C to +85C
2.49
2.63
2.70
Reset Threshold Tempco
30
ppm/
C
V
CC
to Reset Delay (Note 2)
V
CC
= V
TH
to (V
TH
- 100mV)
10
s
Reset Active Timout Period
T
A
= -40
C to +85C
140
256
560
ms
FM803 Output Low
V
OL
V
CC
= V
TH
(min), I
SINK
= 1.2mA,
0.35
V
FM803R/S/T
V
CC
= V
TH
(min), I
SINK
= 3.2mA,
0.4
FM803J/L/M
V
CC
= < 1.0V, I
SINK
= 50
A
0.3
Open-Drain Output Leakage
V
CC
> V
TH
(max), /RESET = 1
7
A
Current
Note 1: Testing in production is 25
C only. V
CC
= 5V for FM803L/M/J, V
CC
= 3.3V for FM803T/S and V
CC
= 3V for FM803R. Limits over temperature are guaranteed by design.
Note 2
Typical values are at 25
C.
4
www.fairchildsemi.com
FM803 3-Pin
C Supervisor Device
www.fairchildsemi.com
FM803 Rev. C.3
Pin Descriptions
Pin Number
Name
Function
1
GND
GROUND
2
/RESET
/RESET remains LOW while V
CC
is below
V
TH
, and for at least 140ms after V
CC
rises
above V
TH
.
3
V
CC
Circuit Timing (Ex: FM803)
When operating properly with 5V V
CC
(for example), /RESET will
also be about 5V. When V
CC
starts to fall, /RESET will follow it
down as shown. When V
CC
drops below V
TH
, /RESET drops to
ground ("issues a RESET") and stays there unless V
CC
also falls
below its minimum operating voltage, approx. 1V. At this point, the
supervisor loses control, and its output may rise, only to again
follow V
CC
down to the ground.
When V
CC
begins to rise, /RESET follows it until 1.0V or so is
reached, whereupon the device regains control, /RESET is pulled
to ground, etc. When V
CC
rises above V
TH
, /RESET comes out of
RESET 140 ms later.
If it is required that a lower value than GND + 1.0V is needed on
RESET signal during V
CC
1V, a 100K resistor may be used on
the device output to GND.
3.3V
V
TH
1V
GND
3.3V
V
TH
1V
GND
V
CC
RESET
140ms
(min)
5
www.fairchildsemi.com
FM803 3-Pin
C Supervisor Device
www.fairchildsemi.com
FM803 Rev. C.3
Ordering Information
Part
Top
RESET
Output
Package
Packing
Number
Marking
Threshold (V)
Type
Type
Method
FM803LS3X
03L
4.63
Open-Drain, active LOW
3-Pin, SOT23
3000 units in T&R
FM803MS3X
03M
4.38
Open-Drain, active LOW
3-Pin, SOT23
3000 units in T&R
FM803JS3X
03J
4.00
Open-Drain, active LOW
3-Pin, SOT23
3000 units in T&R
FM803TS3X
03T
3.08
Open-Drain, active LOW
3-Pin, SOT23
3000 units in T&R
FM803SS3X
03S
2.93
Open-Drain, active LOW
3-Pin, SOT23
3000 units in T&R
FM803RS3X
03R
2.63
Open-Drain, active LOW
3-Pin, SOT23
3000 units in T&R
FM803LP3X
QLY
4.63
Open-Drain, active LOW
3-Pin, SC70
3000 units in T&R
FM803MP3X
QMY
4.38
Open-Drain, active LOW
3-Pin, SC70
3000 units in T&R
FM803JP3X
QJY
4.00
Open-Drain, active LOW
3-Pin, SC70
3000 units in T&R
FM803TP3X
QTY
3.08
Open-Drain, active LOW
3-Pin, SC70
3000 units in T&R
FM803SP3X
QSY
2.93
Open-Drain, active LOW
3-Pin, SC70
3000 units in T&R
FM803RP3X
QRY
2.63
Open-Drain, active LOW
3-Pin, SC70
3000 units in T&R
Note 4: Devices listed above feature 250ms typical Reset Pulse width. Consult Fairchild sales for other reset pulse width options.
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