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Contents

README

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UM811RE

Union Semiconductor · Supervisor And Reset ICs · SOT-143

UM811RE from Union Semiconductor, in a SOT-143. Pinout and pin descriptions extracted from the manufacturer datasheet (extract_pins, cross-checked by a second model); symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin Name Type Function
1 GND power_in Ground reference pin for the supervisor.
2 RESET output Active-low reset output for the UM811 (CMOS push-pull, sources and sinks current); it stays low while VCC is below the reset threshold or while MR is held low, and for the reset active timeout period tRP (140 to 560 ms, 240 ms typical) after reset conditions end.
3 MR input Active-low manual reset input that asserts reset while low and holds reset for 240 ms after returning high, with an internal 20 kΩ (10 to 30 kΩ) pull-up so it can be left open; for the RE version it is driven with VIH of 0.7×VCC minimum and VIL of 0.25×VCC maximum.
4 VCC power_in Monitored supply input (+5 V, +3.3 V or +3 V nominal) with an operating range of 1.0 V to 5.5 V and an absolute maximum rating of -0.3 V to +6.0 V.

Key specifications

Parameter Value
Manufacturer Union Semiconductor
Package SOT-143
Category Power Management (PMIC)
Pins 4

Electrical characteristics

Limits as printed in the datasheet (page.json metadata.characteristics carries them as data).

Parameter Symbol Min Typ Max Unit Conditions Page
VCC Supply Voltage Range VCC 1 5.5 V TA=0°C to +70°C 4
Supply Current ICC 2 5 μA 4
Reset Threshold, R Version VTH+ 2.59 2.63 2.66 V TA=+25°C 4
Reset Threshold, R Version VTH+ 2.55 2.7 V TA=-40°C to +85°C 4
Reset Active Timeout Period tRP 140 240 560 ms 4
VCC to Reset Delay 10 μs Note 3 4
MR Minimum Pulse Width tMR 10 μs 4
MR to Reset Propagation Delay tMD 0.5 μs 4
MR Pull-Up Resistance 10 20 30 kΩ 4
RESET Output Voltage Low (TE/SE/RE/ZE) VOL 0.3 V ISINK=1.2mA, VCC=VTH(MIN) 5
RESET Output Voltage Low VOL 0.3 V ISINK=50μA, VCC>1.0V 5
Reset Threshold Tempco 150 ppm/°C 4
MR Glitch Immunity 100 ns Note 4 4
Supply Voltage VCC -0.3 6 V 3
Input Current, VCC, MR ICC 20 mA 3
Output Current, RESET, RESET IO 20 mA 3
Continuous Power Dissipation PD 320 mW Derate 4mW/°C above 70°C 3
Operating Temperature Range TA -40 105 °C 3
Storage Temperature Range TSTG -65 160 °C 3
Lead Temperature 300 °C Soldering, 10s 3
Wide Operation Temperature TA -40 85 °C 1

CAD (KiCad official)

  • Symbol: UM811RE
  • Footprint: Package_TO_SOT_SMD:SOT-143
  • 3D model: SOT-143 (KiCad packages3D, STEP)
  • 3D model files: um811re-etched.step / um811re-etched.glb carry the MPN laser-etched on the die in a toggleable Adom.LaserEtch group (Fusion-ready); um811re.step / um811re.glb are the bare package body.

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

  • Datasheet: Union Semiconductor datasheet (14 pp, sha256 2765d38a175c536c, retrieved 2026-10-18, tier: lcsc)
  • Extractor: parts-factory 2.0.0 / extract_pins 0.3, primary claude-haiku-5-5 (text), consensus claude-sonnet-5-5 (agreed), guards: pin_guards 0.1: passed. Pins are checked against the footprint pad set and their cited datasheet pages before publish.
  • CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF