FM6332/3/4 3-Pin Ultra-Low-Voltage
µ
C Supervisor Circuits
ADVANCED INFORMATION
April 2001
FM6332/3/4
3-Pin Ultra-Low-Voltage
µ
C Supervisor Circuit
General Description
The FM6332/3/4 are low-power supervisor circuits that monitor a
microprocessor power supply or other system voltage and issue
a reset pulse when a fault condition exists. The threshold voltages
offered accommodate systems with requirements below the com-
mon 5.0V and 3.3V levels.
The devices feature a precision temperature-compensated volt-
age reference and comparator. When V
CC
falls to the threshold
voltage, a RESET pulse is issued, holding the output in the active
state (LOW for FM6333/4 and HIGH for FM6332). When power
rises above V
TH
, the reset remains for approximately 250 ms to
allow the system clock and other circuits to stabilize.
Features
I
Precision monitoring of low-voltage microprocessor systems
I
V
TH
values of 1.60V, 1.80V, 2.00V, 2.20V and 2.30V
I
Low-power: operating current 3.3µA typical
I
Push-pull output on FM6332/3; open-drain output on FM6334
I
Automatic restart of microprocessor after power failure
I
100ms (min) power-on RESET delay
I
Other reset choices available: 32 to 256ms
I
Operating Temperature -40°C to +85°C
I
SOT23 package
Typical Operating Circuit
V
CC
V
CC
Tolerance Detect
& Reset Monitor
Output
Stage
Reset_out
Temp. Compensated
Reference
External Reset
Detection
Connection Diagram
3
FM6332/3/4
1 = GND
2 = RESET/RESET
3 = V
CC
1
2
SOT23 Package
© 2001 Fairchild Semiconductor Corporation
FM6332/3/4 Rev. A.5
1
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FM6332/3/4 3-Pin Ultra-Low-Voltage
µ
C Supervisor Circuits
Each FM6332/3/4 device has the following Identifier (Top Mark on devices will be 32yz, 33yz or 34yz)
Reset Characteristics
RESET THRESHOLD (V
TH
) Identifier # (y) Fairchild Part Number
2.30
2.20
2.00
1.80
1.60
Y
X
U
W
V
FM633_Yz
FM633_Xz
FM633_Uz
FM633_Wz
FM633_Vz
RESET PULSE DURATION (ms)
32
64
128
256
Identifier# (z) Fairchild Part Number
E
F
H
Blank
FM633_yE*
FM633_yF*
FM633_yH*
FM633_y
Note*:
These choices are available upon special request only. Please work with Fairchild Marketing to determine availability.
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FM6332/3/4 Rev. A.5
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FM6332/3/4 3-Pin Ultra-Low-Voltage
µ
C Supervisor Circuits
Absolute Maximum Ratings
Voltage on any pin relative to GND
V
CC
RESET, RESET
Input Current
Output Current (RESET, RESET)
-0.3V to +6.0V
-0.3V to (V
CC
+ 0.3V)
20mA
Storage Temperature Range
20mA
Lead Temperature (soldering, 10s)
+300°C
-65°C to +150°C
Continuous Power Dissipation (T
A
= 70°C)
SOT23-3 (derate 4mW above 70°C)
Operating Temperature Range
300mW
-40°C to +85°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 (V
CC
= V; T
A
= -40
°
C to +85
°
C unless otherwise noted)
Parameter
Operating Voltage
Operating Voltage
Supply Current
Reset Threshold
Reset Threshold
Reset Threshold
Reset Threshold
Reset Threshold
Reset Output Voltage
(FM6333/FM6334)
V
OL
V
OH
Reset Output Voltage
(FM6332)
Reset Timeout Period
V
OL
t
RST
Symbol
V
CC
V
CC
I
CC
V
TH
V
TH
V
TH
V
TH
V
TH
V
OH
FM6332/FM6333
FM6334
No Load
FM633_Y
FM633_X
FM633_U
FM633_W
FM633_V
Conditions
Min
0.8
1.2
3.3
-5%
-5%
-5%
-5%
-5%
Typ
Max
5.5
5.5
µA
Units
V
V
2.30
2.20
2.00
1.80
1.60
+5%
+5%
+5%
+5%
+5%
V
V
V
V
V
V
V
I
SOURCE
= 200µA, V
CC
>1.8V
I
SOURCE
= 500µA, V
CC
>2.7V
I
SINK
= 50µA, V
CC
>1.0V
I
SINK
= 500µA, V
CC
>1.8V
I
SOURCE
= 1µA, V
CC
>1.0V
I
SOURCE
= 200µA, V
CC
>1.8V
I
SINK
= 500µA, V
CC
>1.8V
I
SINK
= 1.2mA, V
CC
>2.7V
0.8V
CC
0.8V
CC
0.4
0.3
0.8V
CC
0.8V
CC
0.3
0.3
175
240
375
V
V
V
V
V
V
ms
3
FM6332/3/4 Rev. A.5
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FM6332/3/4 3-Pin Ultra-Low-Voltage
µ
C Supervisor Circuits
General Description
The FM6332/3/4 feature a highly accurate voltage reference to
which V
CC
is compared. Once V
CC
is below the specified thresh-
old, it will drive the reset line and continue to hold it LOW (HIGH
for FM6332) until V
CC
returns above the threshold and the time for
the reset pulse duration has expired. The FM6332/3/4 are immune
to short negative going transients on the V
CC
line. The placement
of a 0.1µF bypass capacitor as close as possible to the V
CC
pin
provides additional transient immunity.
For a V
CC
value below 0.7V, the FM6332/3/4 do not sink very much
current on the reset pin. This is not a problem in most systems
since common devices are not functional in this range. If the
application requires the supervisor device to work below 0.7V, use
only FM6332/3. If it is desired for the FM6332/3 reset to be
functional below this range, use a 100KΩ pull up for FM6332 (or
pull down, for FM6333) resistor between reset and V
SS
.
4
FM6332/3/4 Rev. A.5
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FM6332/3/4 3-Pin Ultra-Low-Voltage
µ
C Supervisor Circuits
Typical Operating Characteristics
Supply Current Vs. Temperature
8
7
6
I
CC
(µA)
5
4
3
2
1
0
-60
-40
-20
0
20
Temperature (C)
data to be available after characterization
40
60
80
100
Power up Reset Timeout Vs. Temperature
Power Up Reset Timeout (ms)
300
280
260
240
220
200
-60
-40
-20
0
20
40
60
80
100
Temperature (C)
Normalized Reset Threshold Vs. Temperature
1.050
Normalized Threshold
1.025
1.000
0.975
0.950
-60
-40
-20
0
-20
-40
60
80
100
Temperature (C)
data to be available after characterization
5
FM6332/3/4 Rev. A.5
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