Features: Chopper stabilization
Low switchpoint drift over operating temperature range
Low stress sensitivity
Field-programmable for optimized switchpoints
On-chip protection
Supply transient protection
Reverse-battery protection
On-board voltage regulator
3.5 V to 24 V operationSpecifications
- Chopper stabilization
- Low switchpoint drift over operating temperature range
- Low stress sensitivity
- Field-programmable for optimized switchpoints
- On-chip Protection
- Supply transient protection
- Reverse-battery protection
- On-board Voltage Regulator
- 3.5 V to 24 V operation
Supply Voltage, VCC ..........................................28 V
Reverse-Supply Voltage, VRCC .......................18 V
Magnetic Flux Density, B ............................Unlimited
Operating Temperature
Ambient, TA, Range E........................40ºC to 85ºC
Ambient, TA, Range L......................40ºC to 150ºC
Maximum Junction, TJ(max).............................165ºC
Storage Temperature, TS ............... 65ºC to 170ºCDescriptionThe A1185 and A1186 devices are ultrasensitive, two-wire, unipolar, Hall effect switches. The operate point, BOP, can be field-programmed, after final packaging of the sensor and placement into the application. This advanced feature allows the optimization of the sensor switching performance, by effectively accounting for variations caused by mounting tolerances for the device and the target magnet.
A1185 and A1186 family are produced on the Allegro MicroSystems advanced BiCMOS wafer fabrication process, which implements a patented, high-frequency, chopper-stabilization technique that achieves magnetic stability and eliminates the offsets that are inherent in single-element devices exposed to harsh application environments. Commonly found in a number of automotive applications, the A1185 and A1186 devices are utilized to sense: seat track position, seat belt buckle presence, hood/trunk latching, and shift selector position.
Two-wire unipolar switches are particularly advantageous in price-sensitive applications, because A1185 and A1186 require one less wire than the more traditional open-collector output switches. Additionally, the system designer gains inherent diagnostics because output current normally flows in either of two narrowly-specified ranges. This provides distinct current ranges for Iout(H) and Iout(L). Any output current level outside of these two ranges is a fault condition. The A1185 and A1186 devices also features on-chip transient protection, and a Zener clamp to protect against overvoltage conditions on the supply line.
The output current of the A1186 switches HIGH in the presence of a south polarity magnetic field of sufficient strength; and switches LOW otherwise, including when there is no significant magnetic field present. The A1185 has an inverted output current level: switching LOW in the presence of a south polarity magnetic field of sufficient strength, and HIGH otherwise.
A1185 and A1186 are offered in two package styles: LH, a SOT-23W miniature low-profile package for surface-mount applications, and UA, a three-lead ultramini Single Inline Package (SIP) for through-hole mounting. Each package is available in a lead (Pb) free version (suffix, T) with 100% matte tin plated leadframe.
Also see: A1180, A1181, A1182, A1183, and A1184.
Factory-programmed versions are also available. Refer to: A1145, and A1146.
A1185 Data Sheet
