Site
Map • Contact
Us 中文 • English
High-Performance Power ICs and Hall-Effect Sensors
Related Links:
Datasheets:
A3940: Full-Bridge Power MOSFET Controller (PDF)
Selection Guides:
Power Integrated Circuits,
Automotive ICs,
Power Motor Drivers,
Power Motor Drivers - Full-Bridge
Technical Publications:
Power-up Sequencing for the A3940 (PDF)
Press Releases:
A3940: Allegro MicroSystems, Inc. Announces Full-Bridge Pre-Driver IC Targeted at High Power Automotive and Industrial Motors,
Allegro MicroSystems, Inc. Announces Family of Pre-Driver ICs for Driving High Current Automotive and Industrial Actuators
- Home
- / Products
- / Part Numbers
- / A3940
- / Part Numbers
- / Products
A3940
Full-Bridge Power MOSFET Controller
These parts are in production but have been determined to be NOT FOR NEW DESIGN. This classification indicates that sale of this device is currently restricted to existing customer applications. Samples are no longer available.
Refer to A3941 for replacement.
Features
- Drives wide range of n-channel MOSFETs
- Charge pump to boost gate drive at low-battery-input conditions
- Bootstrapped gate drive with charge pump for 100% duty cycle
- Synchronous rectification
- Fault diagnostic output
- Adjustable dead-time cross-conduction protection
- Motor lead short-to-battery and short-to-ground protection
- Undervoltage/overvoltage protection
- -40°C to +150°C, TJ operation
- Thermal shutdown
Description
The A3940KLP and A3940KLW are designed specifically for automotive applications that require high-power motors. Each provides four high-current gate drive outputs capable of driving a wide range of n-channel power MOSFETs in a full-bridge configuration.
Bootstrap capacitors are utilized to provide the above-battery supply voltage required for n-channel FETs. An internal charge pump for the high side allows for dc (100% duty cycle) operation of the bridge.
Protection features include supply under/overvoltage, thermal shutdown, and motor lead short-to-battery and short-to-ground fault notification, and a programmable dead-time adjustment for crossconduction prevention. The overvoltage trip point is user adjustable.
The A3940 is supplied in a choice of two power packages, a 28-pin TSSOP with an exposed thermal pad (package type LP), and a 28-pin wide-body SOIC (package type LW). Both package types are available in lead (Pb) free versions, with 100 % matte-tin leadframe plating (suffix –T).
Functional Block Diagram
| Part Number | Package Type | RoHS Compliant |
Part Composition/ RoHS Data |
Temperature | Comments | Samples | Distributor Stock |
|---|---|---|---|---|---|---|---|
| A3940KLP | 28-lead TSSOP | No | view data | -40 °C to 135 °C | not for new design | samples not available | |
| A3940KLP-T | 28-lead TSSOP | Yes | view data | -40 °C to 135 °C | not for new design | samples not available | |
| A3940KLPTR | 28-lead TSSOP | No | view data | -40 °C to 135 °C | not for new design | samples not available | |
| A3940KLPTR-T | 28-lead TSSOP | Yes | view data | -40 °C to 135 °C | not for new design | samples not available | |
| A3940KLW | 28-lead SOIC | No | view data | -40 °C to 135 °C | not for new design | samples not available | |
| A3940KLW-T | 28-lead SOIC | Yes | view data | -40 °C to 135 °C | not for new design | samples not available | |
| A3940KLWTR | 28-lead SOIC | No | view data | -40 °C to 135 °C | not for new design | samples not available | |
| A3940KLWTR-T | 28-lead SOIC | Yes | view data | -40 °C to 135 °C | not for new design | samples not available |
Allegro's products are not to be used in life support devices or systems, if a failure of an Allegro product can reasonably be expected to cause the failure of that life support device or system, or to affect the safety or effectiveness of that device or system.