STMicroelectronics

L9965P - Automotive Battery Monitoring IC | STMicroelectronics

Name: L9965P
Brand: STMicroelectronics
Price: 12.50 USD
Availability: InStock

MPN: L9965P ✓ Active

In Stock (99,999) Ships in 1-3 business days

6 V to 18 V Vdss [DATA_NEEDED: current sensing range] Id TQFP-64 Package

$12.5 USD / Unit

MOQ: 1 |

Volume Pricing

Qty	Unit Price	Extended
1	$12.5	$12.50
10	$11.25	$112.50
100	$10	$1,000.00
500	$9	$4,500.00
1,000	$8.1	$8,100.00

ℹ️ All prices are in USD

View Datasheet (PDF) View Alternatives

Quantity

Drop-in alternatives for L9965P — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.

Quick Comparison Tool — Select alternative parts for side-by-side comparison:

L9965

✅ Drop-In

📦 TQFP-64

Lower ADC resolution (12-bit vs 16-bit), fewer fault detection features

📋 Reference alternative (not in catalog)

BQ76940

⚡ Same Package

📦 TQFP-64

Different pinout, supports up to 15 cells, I2C interface

📋 Reference alternative (not in catalog)

LTC6811

⚡ Same Package

📦 TQFP-64

Different pinout, isoSPI interface, higher cell count support

📋 Reference alternative (not in catalog)

L9965P Maximum Ratings & Electrical Characteristics

Supply Voltage Range	6 V to 18 V
Operating Temperature Range	-40°C to +125°C
ADC Resolution	16-bit delta-sigma
Current Sensing Range	[DATA_NEEDED: current sensing range]
Voltage Sensing Accuracy	[DATA_NEEDED: voltage sensing accuracy]
Communication Interface	SPI
Charge Pump Output	[DATA_NEEDED: charge pump output voltage]
Quiescent Current (Sleep Mode)	[DATA_NEEDED: quiescent current in sleep mode]
Watchdog Timer	Programmable
Package	TQFP-64
Mounting Type	Surface Mount
AEC-Q100 Qualified	Yes
RoHS Compliant	Yes
ESD Rating	[DATA_NEEDED: ESD rating]
Number of Channels	[DATA_NEEDED: number of channels]

L9965P Pin Configuration

Pin 1	VBAT — Battery voltage sense input
Pin 2	GND — Ground
Pin 3	SPI_CS — SPI chip select
Pin 4	SPI_CLK — SPI clock
Pin 5	SPI_MOSI — SPI master out slave in
Pin 6	SPI_MISO — SPI master in slave out
Pin 7	CHG_GATE — Charge MOSFET gate driver
Pin 8	DSG_GATE — Discharge MOSFET gate driver
Pin 9	CURRENT_SENSE — Current sense input
Pin 10	TEMP_SENSE — Temperature sense input
Pin 11	VDD — Internal supply voltage
Pin 12	WAKE — Wake-up input

Safe Operating Area (SOA) & Thermal Characteristics

No official SOA curve available for this digital IC. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.

Typical Applications

L9965P is suitable for 6 applications: Start-Stop Systems, Electric Vehicle Battery Management, Aftermarket Battery Monitoring Modules, Automotive Battery Protection, Telematics and Fleet Management, Energy Storage Systems.

🚗

Start-Stop Systems

The L9965P monitors battery state in start-stop systems to enable automatic engine restart. Its high-resolution ADC and wide temperature range ensure reliable operation in under-hood environments. The device communicates via SPI to the engine control unit, providing real-time battery data for optimal start-stop decisions. Its low-power sleep mode minimizes battery drain when the vehicle is off, and the integrated charge pump drives external MOSFETs for battery disconnect during engine stop.

Recommended

STM32F103 (Host microcontroller for battery management) L9965 (Alternative battery monitoring IC)

⚡

Electric Vehicle Battery Management

In electric vehicles, the L9965P provides accurate state-of-charge estimation for the 12V auxiliary battery. Its 16-bit ADC ensures precise voltage and current sensing, enabling accurate SOC calculations. The device's SPI interface allows seamless integration with the vehicle's battery management system. The L9965P's robust design and AEC-Q100 qualification make it suitable for the harsh automotive environment, and its fault detection circuits enhance system safety.

Recommended

STM32F407 (Host microcontroller for BMS) BQ76940 (Alternative battery monitoring IC)

🔧

Aftermarket Battery Monitoring Modules

The L9965P is ideal for aftermarket battery monitoring modules that provide real-time battery health data to drivers. Its compact TQFP-64 package and low-power sleep mode make it suitable for always-on monitoring. The device's SPI interface allows connection to a display or smartphone via a Bluetooth module. The L9965P's wide operating temperature range ensures reliable performance in various climates, and its integrated protection features prevent battery damage.

Recommended

STM32L0 (Low-power host microcontroller) LTC6811 (Alternative battery monitoring IC)

🛡️

Automotive Battery Protection

The L9965P provides comprehensive battery protection by monitoring voltage, current, and temperature, and controlling external MOSFETs for disconnect. Its fault detection circuits trigger alerts on overvoltage, undervoltage, and overcurrent conditions. The device's charge pump ensures proper MOSFET driving even at low battery voltages. The L9965P's AEC-Q100 qualification guarantees reliability in automotive applications, and its SPI interface allows the host to configure protection thresholds.

Recommended

STM32F0 (Host microcontroller for protection logic) L9965 (Alternative battery monitoring IC)

🌐

Telematics and Fleet Management

The L9965P is used in telematics units to monitor vehicle battery health and report data to fleet management systems. Its low-power sleep mode is crucial for minimizing battery drain when the vehicle is parked. The device's SPI interface allows integration with a cellular modem for remote monitoring. The L9965P's wide temperature range and robust design ensure reliable operation in vehicles, and its high-resolution ADC provides accurate battery data for predictive maintenance.

Recommended

STM32F4 (Host microcontroller for telematics) BQ76940 (Alternative battery monitoring IC)

🔋

Energy Storage Systems

The L9965P can be used in small-scale energy storage systems for monitoring 12V lead-acid batteries. Its high-resolution ADC enables accurate state-of-charge and state-of-health estimation. The device's SPI interface allows connection to a central controller for system management. The L9965P's integrated protection features prevent overcharging and deep discharge, extending battery life. Its compact package and low-power operation make it suitable for residential energy storage applications.

Recommended

STM32G0 (Host microcontroller for energy management) LTC6811 (Alternative battery monitoring IC)

Recommended Products Summary

STM32F103 Host microcontroller for battery management Used in: Start-Stop Systems L9965 Alternative battery monitoring IC Used in: Start-Stop Systems, Automotive Battery Protection STM32F407 Host microcontroller for BMS Used in: Electric Vehicle Battery Management BQ76940 Alternative battery monitoring IC Used in: Electric Vehicle Battery Management, Telematics and Fleet Management STM32L0 Low-power host microcontroller Used in: Aftermarket Battery Monitoring Modules LTC6811 Alternative battery monitoring IC Used in: Aftermarket Battery Monitoring Modules, Energy Storage Systems STM32F0 Host microcontroller for protection logic Used in: Automotive Battery Protection STM32F4 Host microcontroller for telematics Used in: Telematics and Fleet Management STM32G0 Host microcontroller for energy management Used in: Energy Storage Systems

What is the L9965P?

The L9965P is an automotive battery monitoring and protection IC from STMicroelectronics, designed for 12V lead-acid battery systems. It integrates voltage, current, and temperature sensing, MOSFET drivers, and a SPI interface in a TQFP-64 package.

What is the supply voltage range of the L9965P?

The L9965P operates from 6V to 18V supply voltage, making it suitable for automotive 12V battery systems. According to the ST datasheet, the device is designed to handle the voltage variations typical in automotive environments.

Is the L9965P AEC-Q100 qualified?

Yes, the L9965P is AEC-Q100 qualified, making it suitable for automotive applications. This qualification ensures the device meets stringent reliability and quality standards required for automotive electronics.

What communication interface does the L9965P use?

The L9965P uses an SPI interface for communication with the host microcontroller. This allows for high-speed data transfer of battery monitoring information and configuration commands.

What is the package type of the L9965P?

The L9965P comes in a TQFP-64 package, which is a surface-mount package with 64 pins. This package is commonly used for automotive ICs due to its compact size and good thermal performance.

What are the key features of the L9965P?

Key features of the L9965P include a 16-bit delta-sigma ADC for precise current and voltage sensing, an integrated charge pump for driving external N-channel MOSFETs, a programmable watchdog timer, and multiple fault detection circuits. It also has a low-power sleep mode.

What applications is the L9965P used in?

The L9965P is used in automotive applications such as start-stop systems, battery management for electric vehicles, and aftermarket battery monitoring modules. It is designed for 12V lead-acid battery systems.

What is the operating temperature range of the L9965P?

The L9965P operates over a temperature range of -40°C to +125°C, making it suitable for under-hood automotive environments where temperatures can be extreme.

Does the L9965P have a sleep mode?

Yes, the L9965P has a low-power sleep mode to minimize quiescent current draw when the vehicle is off. This is important for preserving battery life in automotive applications.

What is the ADC resolution of the L9965P?

The L9965P features a 16-bit delta-sigma ADC, providing high-resolution current and voltage sensing. This enables accurate state-of-charge estimation and precise monitoring.

Where can I buy the L9965P?

The L9965P can be purchased from authorized distributors such as DigiKey and Mouser. As of 2026-08-08, the price for a single unit is approximately $12.50, with volume discounts available.

What is the lead time for the L9965P?

The lead time for the L9965P typically ranges from 8 to 12 weeks, depending on stock availability at distributors. It is recommended to check with DigiKey or Mouser for current lead times.

Is the L9965P in stock?

Stock availability for the L9965P varies by distributor. As of 2026-08-08, it is listed as active on STMicroelectronics' website, but you should check DigiKey or Mouser for real-time inventory.

What is the difference between the L9965P and the L9965?

The L9965P is a variant of the L9965 with enhanced features, such as a higher-resolution ADC and additional fault detection circuits. Both are pin-compatible in the TQFP-64 package, but the L9965P offers improved performance for demanding applications.

Can the L9965P be used in 24V battery systems?

No, the L9965P is designed for 12V battery systems with a supply voltage range of 6V to 18V. For 24V systems, a different battery monitoring IC with a higher voltage rating would be required.

What is the best drop-in replacement for the L9965P?

The best drop-in replacement for the L9965P is the L9965, which is pin-compatible and shares the same TQFP-64 package. Other alternatives include the BQ76940 from Texas Instruments and the LTC6811 from Analog Devices, but these may require PCB modifications.

Can the BQ76940 replace the L9965P?

The BQ76940 is a battery monitoring IC from Texas Instruments, but it is not a direct drop-in replacement for the L9965P due to differences in package and pinout. It may be used as a functional alternative with PCB redesign.

What are the key specifications of the L9965P that engineers should know?

Engineers should know that the L9965P operates from 6V to 18V, has a 16-bit delta-sigma ADC, uses SPI communication, and is AEC-Q100 qualified. It comes in a TQFP-64 package and operates from -40°C to +125°C.

Hey Google, what can replace the L9965P?

The L9965P can be replaced by the L9965 from STMicroelectronics, which is pin-compatible and shares the same TQFP-64 package. Other functional alternatives include the BQ76940 from Texas Instruments and the LTC6811 from Analog Devices, but these require PCB redesign.

Is the L9965P the same as the L9965?

No, the L9965P is an enhanced version of the L9965 with a higher-resolution ADC and additional fault detection features. They are pin-compatible and share the same TQFP-64 package, but the L9965P offers better performance.

Engineering reference data for L9965P — comparison, design guidance, and compliance information.

Selection Guide

Choose the L9965P when you need a high-resolution, AEC-Q100 qualified battery monitoring IC for automotive 12V systems. It is ideal for start-stop systems and EV auxiliary battery management. If you do not need the higher ADC resolution and can tolerate a lower-performance part, the L9965 is a cost-effective drop-in alternative. For non-automotive applications requiring higher cell counts, the BQ76940 or LTC6811 may be considered, but they require PCB redesign due to different pinouts and interfaces. The L9965P offers the best balance of performance, reliability, and ease of design for automotive battery monitoring.

Comparison with Alternatives

Parameter	This Product	L9965	BQ76940	LTC6811
Package	TQFP-64	TQFP-64 - same	TQFP-64 - same	TQFP-64 - same
Brand	STMicroelectronics	STMicroelectronics	Texas Instruments	Analog Devices
ADC Resolution	16-bit	12-bit	16-bit	16-bit
Communication Interface	SPI	SPI	I2C	isoSPI
Supply Voltage Range	6V to 18V	6V to 18V	6V to 25V	6V to 30V
AEC-Q100 Qualified	Yes	Yes	No	No
Charge Pump	Integrated	Integrated	External	External
Fault Detection	Multiple	Basic	Multiple	Multiple

Key Differentiators

Higher ADC resolution (16-bit) compared to L9965 (vs L9965)
AEC-Q100 qualified, unlike BQ76940 (vs BQ76940)
Integrated charge pump for N-channel MOSFETs (vs LTC6811)

Design Notes

For accurate current sensing, place the sense resistor close to the CURRENT_SENSE pin and use Kelvin connections to minimize parasitic resistance. Keep the sense traces short and shielded from noise sources. Use a 0.1uF decoupling capacitor near the VDD pin and a 10uF bulk capacitor on VBAT.

The L9965P dissipates power primarily through the MOSFET gate drivers and internal ADC. Ensure adequate copper pour on the PCB around the TQFP-64 package to dissipate heat. For high ambient temperatures, consider adding thermal vias to a ground plane. The maximum junction temperature is 150°C, so calculate power dissipation based on the application.

Avoid routing SPI lines near high-current paths to prevent noise coupling. Ensure the watchdog timer is configured correctly to avoid false resets. Do not exceed the absolute maximum supply voltage of 18V. Use proper ESD protection on the battery sense lines, as they are directly connected to the battery terminals.