Original Honeywell SS443A TO-92S Package Sensor

Original Honeywell SS443A TO-92S Package Sensor

Specifications

Sensor Type: Unipolar Hall switch (triggers only with S-pole south)
Package: TO-92-Flat-3 (TO-92S flat 3-pin, through-hole); SMD version: SS443A-S (SOT-89)
Supply Voltage: 3.8VDC ~ 30VDC, compatible with 5/12/24V systems
Quiescent Current: Typical 10 mA
Output Type: Open-collector NPN output, requires external pull-up resistor; max sinking current 20 mA
Response Frequency: Up to 20 kHz, suitable for speed counting and high-speed detection
Operating Temperature: -40℃ ~ 150℃ (industrial high temp)
Protection: Built-in reverse polarity protection; RoHS compliant

Magnetic Switch Threshold (25℃)
Gauss / milliTesla conversion: 1 mT = 10 Gs
Operate Point Bop (magnet approaches, output pulled low): 110~180 Gs (11‑18 mT), typical 125 Gs
Release Point Brp (magnet moves away, output returns high impedance): 75‑155 Gs (7.5‑15.5 mT), typical 90 Gs
Built-in hysteresis prevents false triggering due to magnetic fluctuations

Pinout (TO-92S flat, with printed side facing you, pins down, left to right)
Pin1: VCC +3.8-30V
Pin2: GND
Pin3: OUT (open-collector output)
⚠️Important: Pin3 is open-collector and cannot directly connect to MCU IO; external pull-up resistor (1k-10k) to IO voltage is required.

Operating Logic
No magnetic field / N-pole nearby: output is high-impedance (reads high after pull-up)
S-pole magnetic field above Bop: output pulled to GND (low)
Magnetic field below Brp: output returns to high-impedance/high

Typical Applications
Speed detection, motor Hall speed sensing, gear counting
Magnet approach detection, limit switches, door sensors
Industrial high-temp position detection; 12V/24V magnetic detection
Distinguishing same-series models

 Honeywell SS443A TO-92S Package Sensor