L9965P-FP-TR - Single Channel Pyro-Fuse Driver | STMicroelectronics
MPN: L9965P-FP-TR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.2 | $5.20 |
| 10 | $4.78 | $47.80 |
| 100 | $4.25 | $425.00 |
| 500 | $3.85 | $1,925.00 |
| 1,000 | $3.42 | $3,420.00 |
L9965P-FP-TR Overview
A pyro-fuse driver is a specialized safety IC in the power management category that interfaces the battery management system (BMS) or airbag control unit to a pyrotechnic disconnect element. Its job is to deliver a precisely controlled energy pulse to the initiator, rapidly opening the high-current battery loop when a crash or fault is detected, before conventional contactors can react. This places the pyro-fuse driver in the safety-critical branch of the vehicle electrical system, sitting between the BMS microcontroller and the high-voltage bus.
Key features include integrated HS+LS powerMOS output stage, automotive-grade qualification, single-channel architecture, and a thermally enhanced TQFP-32 package with exposed pad for board-level heat spreading. The dual-FET topology lets the device source and sink current through the initiator, which improves switching symmetry and reduces residual magnetic energy. The L9965P is intended to operate alongside a host microcontroller that commands ignition via a logic-level trigger.
Typical applications include high-voltage battery disconnect in BEV (battery electric vehicle) and HEV (hybrid electric vehicle) powertrains, e-fuse replacement for crash-triggered isolation, and pyrotechnic safety circuits coordinated with airbag ECUs. The 32-TQFP footprint is compatible with standard reflow profiles used in automotive PCB assembly.
Designers should follow the reference schematic and PCB layout in the ST evaluation board EVL9965P-N. The exposed pad must be soldered to a sufficient copper pour to keep junction temperature within automotive limits during the brief but high-current ignition event. Loop inductance of the initiator traces should be minimized to avoid voltage overshoot on the FET outputs.
Drop-in alternatives for L9965P-FP-TR — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with L9965P-FP-TR (same form factor and footprint) — differing in Output Stage, Package, Product Type, RoHS Status.
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L9965P-FP
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View Datasheet →L9965P-FN-TR
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View Datasheet →L9965P-FN
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
L9965P-FP-TR Specifications
| Product Type | Single-channel pyro-fuse driver |
| Topology | Dual FET (HS + LS) powerMOS output stage |
| Number of Channels | 1 |
| Package | TQFP-32 (7x7 mm) with exposed pad |
| Mounting Type | Surface Mount |
| Automotive Grade | Yes (automotive-qualified per ST product page) |
| Operating Mode | Triggered single-shot energy pulse to pyrotechnic initiator |
| Output Stage | Integrated high-side + low-side powerMOS |
| Trigger Input | Logic-level command from host MCU |
| Application Domain | High-voltage battery disconnect, crash-triggered isolation |
| Compatible Evaluation Board | EVL9965P-N |
| RoHS Status | Compliant |
| Lead-Free | Yes (per ST product family standard) |
L9965P-FP-TR tqfp-32 (7x7 mm) with exposed pad Pin Configuration Guide
Pin configuration for L9965P-FP-TR (tqfp-32 (7x7 mm) with exposed pad package). Pin numbering, functions, and connection diagrams are defined in the manufacturer datasheet. Refer to it for the exact footprint and soldering guidelines.
No detailed pinout data available for L9965P-FP-TR.
Refer to the datasheet for full pin configuration.
Typical Applications
L9965P-FP-TR is suitable for 6 applications: BEV/HEV High-Voltage Battery Disconnect, Crash-Triggered Pyrotechnic Isolation, Pyrotechnic E-Fuse Replacement, EV Battery Management System (BMS) Safety Subsystem, Industrial High-Voltage Disconnect Systems, Safety ECU Integration with Airbag Controller.
BEV/HEV High-Voltage Battery Disconnect
The L9965P-FP-TR is purpose-built to drive a pyrotechnic initiator that physically severs a high-voltage battery busbar during a crash or short-circuit event in battery electric and hybrid vehicles. Its integrated HS+LS powerMOS output stage delivers the controlled energy pulse required by the initiator with sub-millisecond response, far faster than mechanical contactors. The 32-TQFP package with exposed pad dissipates the brief but high-current ignition pulse while keeping junction temperature within automotive limits when soldered to adequate copper.
Recommended
Crash-Triggered Pyrotechnic Isolation
In a crash event, the L9965P-FP-TR is commanded by the airbag ECU or BMS controller to fire the pyro-fuse initiator within microseconds of crash detection, isolating the high-voltage system from the rest of the vehicle before rescue operations begin. The dual-FET output stage provides both source and sink current paths through the initiator, ensuring symmetric switching and minimal residual magnetic energy. The automotive-grade qualification and the safety-critical design of the output stage make it suitable for ASIL-rated systems.
Recommended
Pyrotechnic E-Fuse Replacement
The L9965P-FP-TR replaces slower electromechanical e-fuses in next-generation EV battery packs by providing a one-shot, ultra-fast disconnect mechanism with no moving parts. The HS+LS powerMOS stage simplifies the external circuitry by eliminating the need for separate high-side and low-side drivers, while the TQFP-32 footprint enables compact PCB placement near the initiator. Compared with semiconductor-only e-fuses, the pyro-fuse approach avoids continuous conduction losses and thermal stress in normal operation.
Recommended
EV Battery Management System (BMS) Safety Subsystem
Inside a high-voltage BMS, the L9965P-FP-TR is paired with a host microcontroller and current-sensing circuitry to form a dedicated safety subsystem that monitors for short-circuit or crash events and triggers pyrotechnic isolation. The integrated dual-FET stage accepts a logic-level command from the MCU and converts it into the high-current pulse required by the initiator, freeing the host from managing high-current switching directly. The 32-TQFP footprint integrates cleanly alongside other BMS ICs on a single safety board.
Recommended
Industrial High-Voltage Disconnect Systems
Outside of passenger vehicles, the L9965P-FP-TR can serve in industrial high-voltage battery banks, energy-storage systems, and railway traction battery packs where rapid crash-equivalent isolation is required. The automotive-grade qualification provides margin in harsh industrial environments, while the TQFP-32 package is compatible with standard SMT lines used in industrial assembly. The dual-FET output stage supports reliable one-shot triggering under wide operating conditions.
Recommended
Safety ECU Integration with Airbag Controller
The L9965P-FP-TR is often co-located with an airbag control unit on the vehicle's safety ECU, sharing crash sensor inputs to coordinate airbag deployment with high-voltage battery isolation. Its logic-level trigger interface accepts a single GPIO-style command from the airbag MCU, while the HS+LS output stage handles the heavy current pulse to the initiator. The exposed-pad TQFP-32 package dissipates the brief ignition pulse without requiring an external heatsink.
Recommended
Recommended Products Summary
Engineering reference data for L9965P-FP-TR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | L9965P-FP | L9965P-FN-TR | L9965P-FN |
|---|---|---|---|---|
| Package | TQFP-32 (7x7 mm) | TQFP-32 (7x7 mm) - same | VFQFPN-32 (5x5 mm) - different package | VFQFPN-32 (5x5 mm) - different package |
| Brand | STMicroelectronics | STMicroelectronics | STMicroelectronics | STMicroelectronics |
| Product Type | Single-channel pyro-fuse driver | Single-channel pyro-fuse driver | Single-channel pyro-fuse driver | Single-channel pyro-fuse driver |
| Output Stage | Integrated HS + LS powerMOS | Integrated HS + LS powerMOS | Integrated HS + LS powerMOS | Integrated HS + LS powerMOS |
| Automotive Grade | Yes | Yes | Yes | Yes |
| Carrier Format | Tape & Reel | Tube | Tape & Reel (QFN) | Tube (QFN) |
| Compatible Evaluation Board | EVL9965P-N | EVL9965P-N | EVL9965P-N | EVL9965P-N |
| Datasheet | l9965p.pdf | l9965p.pdf | l9965p.pdf | l9965p.pdf |
Key Differentiators
- Integrated HS+LS powerMOS output stage (vs Discrete pyro-fuse driver using external FETs)
- Automotive-grade qualification (vs Industrial-grade pyro-fuse drivers)
- TQFP-32 footprint with exposed pad (vs Non-TQFP competitor packages)
Design Notes
The L9965P-FP-TR TQFP-32 package includes an exposed thermal pad that must be soldered to a continuous copper pour on the PCB. Although the pyro-fuse event is single-shot and brief, the high peak current through the HS+LS powerMOS stage creates localized heating. ST's EVL9965P-N reference design uses a multi-layer board with at least 1 square inch of top-layer copper tied to the exposed pad to keep junction temperature rise within automotive derating limits.
Minimize loop inductance between the L9965P-FP-TR output pins and the pyrotechnic initiator by routing the HS and LS paths as a tight, symmetric differential pair with wide traces. According to ST's datasheet, residual inductance can cause voltage overshoot across the powerMOS outputs that may exceed the device ratings. Place a decoupling capacitor as close as possible to the device supply pin and follow the EVL9965P-N reference layout for first-pass success.
Do not use the L9965P-FP-TR as a continuously-conducting switch; it is designed for single-shot, triggered ignition events only. Repeated or prolonged activation will exceed the safe operating area of the integrated powerMOS stage. Designers must also ensure the host MCU provides a clean, debounced trigger command and that the system-level safety case prevents accidental firing during maintenance or vehicle service.
Keep the trigger logic traces (MCU GPIO to L9965P-FP-TR EN/TRIG input) physically separated from the high-current initiator traces to avoid coupling noise into the command path. According to ST's reference documentation, a ground guard trace around the logic-level inputs improves noise immunity. Use the EVL9965P-N evaluation board layout as the gold-standard reference for production PCB designs.
Compliance Information
Automotive-grade per ST product page. AEC-Q100 qualification assumed from automotive positioning; verify exact grade in datasheet. RoHS/REACH compliance inferred from ST standard product family practice.
