Document
3197
PROTECTED, HIGH-TEMPERATURE, OPEN-COLLECTOR HALL-EFFECT LATCH
These open-collector Hall-effect latches are capable of sensing magnetic fields while using an unprotected power supply. The A3197LLT and A3197LU can provide position and speed information by providing a digital output for magnetic fields that exceed their predefined switch points. These devices operate down to zero speed and have switch points that are designed to be extremely stable over a wide operating temperature and voltage range. The latching characteristics make them ideal for use in pulse counting applications when used with a multi-pole ring magnet. Thermal and output short-circuit protection allow an increased wiring harness fault tolerance. The temperature compensated switch points, the wide operating voltage range, and the integrated protection make these devices ideal for use in automotive applications such as transmission speed sensors and integrated wheel bearing speed sensors.
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Data Sheet 27609.10A
X
PTCT
V
CC
1
2
Dwg. PH-003-2
Each monolithic device contains an integrated Hall-effect transducer, a temperature-compensated comparator, a voltage regulator, and a buffered 35 mA output sink stage. Supply protection is made possible by the integration of overvoltage and undervoltage shutdown circuitry that monitor supply fault conditions and shut down the IC. Noise shutdown circuitry (patent applied for) prevents the propagation of supply transients to the logic load. Output protection circuitry includes a current limit loop that limits the maximum output sink current, and thermal protection circuitry that shuts down the device during an over-heating condition such as with a shorted load. The A3197LLT and A3197LU are rated for operation over an extended temperature range of -40°C to +150°C. They are supplied in a three-lead SIP (suffix ‘U’) or a surface-mount SOT-89 (suffix ‘LT’).
GROUND
ABSOLUTE MAXIMUM RATINGS
Supply Voltage, VCC (100 ms) ................................... 115 V* (continuous) ............................... 28 V* Reverse Battery Voltage, VRCC (100 ms) ................................... -100 V (continuous) ............................... -35 V Magnetic Flux Density, B .......... Unlimited Output OFF Voltage, VOUT ................. 26 V Reverse Output Voltage VOUT ......... -0.5 V Continuous Output Current, IOUT .......................................... 35 mA* Reverse Output Current, IOUT ........................................ -100 mA Package Power Dissipation, PD ....................................... See Graph Junction Temperature, TJ ................. 170°C Operating Temperature Range, TA .......................................... -40°C to +150°C Storage Temperature, TS .................. 170°C
*Fault condition, internal overvoltage shutdown above 28 V; output current limited above 35 mA.
OUTPUT
SUPPLY
FEATURES
I I I I I I I I I I Internal Protection For Automotive (ISO/DIN) Transients Operation From Unregulated Supply Reverse .