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www.fairchildsemi.com
F
FM1233 Rev. A
FM1233
Precision Reset Generator Circuit
Block Diagram
August 2000
2000 Fairchild Semiconductor International
General Description
The FM1233 features comprehensive reset generation for
microcontroller/microprocessor based systems. If the system V
CC
voltage level is determined to be in an out-of-tolerance state, the
device automatically generates a low-going reset signal. The
reset signal is held in the active state (low) for a specified duration
(minimum 140 ms) after the V
CC
returns to an in-tolerance state.
The FM1233 also allows an external reset to be connected to the
reset pin without adding aditional debounce logic or extra pins.
This device is fabricated using CMOS technology. This device is
available in the SOT-23 package.
Features
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Automatic reset generation on power-up
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Minimum 140 ms reset pulse — compatible with other similar
1233 class devices
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Other reset pulse choices available: 32 - 256 ms
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Choice of commercial and extended temperature ranges
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Choice of Reset Thresholds: 4.63V, 4.38V, 4.00V, 3.08V,
2.93V, 2.63V
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Package available: SOT-23
Connection Diagram
1
2
3
FM1233
1 = GND
2 = RESET'
3 = V
CC
V
CC
Tolerance Detect
& Reset Monitor
V
CC
Temp. Compensated
Reference
Output
Stage
Reset_out
(active low)
External Reset
Detection