Product Overview
The A1120, A1121, A1122, A1123, and A1125 are highly temperature-stable and stress-resistant Hall-effect unipolar switches designed for operation in extended temperature ranges up to 150C. Featuring dynamic offset cancellation for superior high-temperature performance, these ICs integrate a voltage regulator, Hall-voltage generator, amplifier, chopper stabilization, Schmitt trigger, and a short-circuit protected open-drain output. They operate from supply voltages of 3 to 24 V, with an advantage of low-voltage operation down to 3 V for 3 V applications or enhanced protection against transients. The A1120-A1123 activate with a sufficient south pole magnetic field, while the A1125 is complementary. Available in surface-mount SOT23W (LH) and through-hole SIP (UA) packages, these lead-free devices offer solid-state reliability and small package sizes.
Product Attributes
- Brand: Allegro MicroSystems
- Certifications: AEC-Q100 automotive qualified
- Material: Lead (Pb) free with 100% matte-tin-plated leadframe
- Origin: U.S.A.
Technical Specifications
| Part Number | Mounting | Ambient Temp. (C) | Output In South Pole (Typ. G) | Output Off South Pole (Typ. G) | Output State |
| A1120ELHLX-T | 3-pin SOT23W surface mount | 40 to 85 | 35 | 25 | On (logic low) |
| A1120LLHLX-T | 3-pin SOT23W surface mount | 40 to 150 | 35 | 25 | On (logic low) |
| A1120EUA-T | 3-pin SIP through hole | 40 to 85 | 35 | 25 | On (logic low) |
| A1120LUA-T | 3-pin SIP through hole | 40 to 150 | 35 | 25 | On (logic low) |
| A1121ELHLX-T | 3-pin SOT23W surface mount | 40 to 85 | 95 | 70 | On (logic low) |
| A1121LLHLX-T | 3-pin SOT23W surface mount | 40 to 150 | 95 | 70 | On (logic low) |
| A1121EUA-T | 3-pin SIP through hole | 40 to 85 | 95 | 70 | On (logic low) |
| A1121LUA-T | 3-pin SIP through hole | 40 to 150 | 95 | 70 | On (logic low) |
| A1122ELHLX-T | 3-pin SOT23W surface mount | 40 to 85 | 150 | 125 | On (logic low) |
| A1122LLHLX-T | 3-pin SOT23W surface mount | 40 to 150 | 150 | 125 | On (logic low) |
| A1122EUA-T | 3-pin SIP through hole | 40 to 85 | 150 | 125 | On (logic low) |
| A1122LUA-T | 3-pin SIP through hole | 40 to 150 | 150 | 125 | On (logic low) |
| A1123LLHLX-T | 3-pin SOT23W surface mount | 40 to 150 | 280 | 225 | On (logic low) |
| A1123LUA-T | 3-pin SIP through hole | 40 to 150 | 280 | 225 | On (logic low) |
| A1125ELHLX-T | 3-pin SOT23W surface mount | 40 to 85 | 35 | 25 | Off (logic high) |
| A1125LLHLX-T | 3-pin SOT23W surface mount | 40 to 150 | 35 | 25 | Off (logic high) |
| A1125EUA-T | 3-pin SIP through hole | 40 to 85 | 35 | 25 | Off (logic high) |
| A1125LUA-T | 3-pin SIP through hole | 40 to 150 | 35 | 25 | Off (logic high) |
| Characteristic | Symbol | Min. | Typ. | Max. | Unit | Notes |
| Forward Supply Voltage | VCC | 3 | | 24 | V | Operating, TJ < 165C |
| Output Leakage Current | IOUTOFF | | | 10 | A | VOUT = 24 V, B < BRP (A1120-A1123); VOUT = 24 V, B > BOP (A1125) |
| Output Saturation Voltage | VOUT(SAT) | | 185 | 500 | mV | IOUT = 20 mA, B > BOP (A1120-A1123); IOUT = 20 mA, B < BRP (A1125) |
| Output Current Limit | IOM | 30 | | 60 | mA | B > BOP (A1120-A1123); B < BRP (A1125) |
| Power-On Time | tPO | | | 25 | s | VCC > 3.0 V, B < BRP(min) or B > BOP(max) |
| Chopping Frequency | fC | | 800 | | kHz | |
| Output Rise Time | tr | | 0.2 | 2 | s | RL = 820 , CS = 20 pF |
| Output Fall Time | tf | | 0.1 | 2 | s | RL = 820 , CS = 20 pF |
| Supply Current (ON) | ICC(ON) | | | 4 | mA | VCC = 12 V, B > BOP (A1120-A1123); VCC = 12 V, B < BRP (A1125) |
| Supply Current (OFF) | ICC(OFF) | | | 4 | mA | VCC = 12 V, B < BRP (A1120-A1123); VCC = 12 V, B > BOP (A1125) |
| Reverse Supply Current | IRCC | | | -5 | mA | VRCC = 30 V |
| Supply Zener Clamp Voltage | VZ | 28 | | | V | ICC = 5 mA; TA = 25C |
| Zener Impedance | IZ | | 50 | | | ICC = 5 mA; TA = 25C |
| Characteristic | Symbol | Min. | Typ. | Max. | Unit |
| Operate Point | BOP | | 35 | 50 | G | A1120, A1125 |
| Operate Point | BOP | 50 | 95 | 135 | G | A1121 |
| Operate Point | BOP | 120 | 150 | 200 | G | A1122 |
| Operate Point | BOP | 205 | 280 | 355 | G | A1123 |
| Release Point | BRP | 5 | 25 | | G | A1120, A1125 |
| Release Point | BRP | 40 | 70 | 110 | G | A1121 |
| Release Point | BRP | 110 | 125 | 190 | G | A1122 |
| Release Point | BRP | 150 | 225 | 300 | G | A1123 |
| Hysteresis | BHYS | | 10 | | G | A1120, A1125 |
| Hysteresis | BHYS | 10 | 25 | 42 | G | A1121, A1122 |
| Hysteresis | BHYS | 30 | 55 | 80 | G | A1123 |
