L9956 - SPI Controlled 8-Channel Low-Side Driver | STMicroelectronics
MPN： L9956 ✓ 啟用中L9956 概覽
A low-side driver is a type of power switch that connects the load to ground when activated, commonly used in automotive body control modules, industrial automation, and lighting systems. In the broader system hierarchy, the L9956 functions as a power management IC, specifically a smart power switch, which integrates control logic, protection features, and power transistors into a single device. This integration reduces external component count, improves reliability, and simplifies PCB design compared to discrete implementations.
Key features of the L9956 include SPI (Serial Peripheral Interface) control for advanced diagnostics and configuration, 8-bit PWM capability for dimming or proportional control, and comprehensive protection features such as overcurrent, overtemperature, and open-load detection. The device also features a low quiescent current in standby mode, making it ideal for battery-powered applications. The SPI interface allows real-time monitoring of output status and fault conditions, enabling robust system-level diagnostics.
From a technical perspective, the L9956 utilizes a smart power technology that combines CMOS logic with vertical power MOSFETs, achieving low on-resistance (typically 0.5 ohm per channel) and fast switching speeds. The device includes a built-in charge pump to drive the high-side gate of the output transistors, ensuring efficient operation even at low battery voltages. The SPI interface operates at clock frequencies up to 5 MHz, supporting high-speed communication with microcontrollers.
Typical applications include automotive body control modules (BCMs) for controlling exterior and interior lighting, relay replacement in industrial control systems, and driving solenoids or valves in automation equipment. The L9956's ability to handle inductive loads with built-in freewheeling diodes makes it particularly suitable for driving relays and solenoids without external clamping components.
When designing with the L9956, it is essential to ensure proper thermal management by providing adequate copper area on the PCB for heat dissipation, especially when operating multiple channels at high current simultaneously. Additionally, the SPI lines should be properly terminated and protected against ESD to maintain reliable communication in harsh automotive environments.
直接替換替代品，適用於 L9956 — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： L9956 （相同外形與佔位） — 差異在於 Package, Mounting Type, Number of Channels, Diagnostics, Operating Temperature Range.
L9956XP
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
L9955
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →L9958
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →TLE6228GP
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
MC33882
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
L9956 最大額定值與電氣特性
| Number of Channels | 8 |
| 輸出類型 | Low-Side |
| Maximum Output Current per Channel | 1.5 A |
| Supply Voltage (Logic) | 4.5 V to 5.5 V |
| Supply Voltage (Power) | 4.5 V to 28 V |
| On-Resistance (Typical) | 0.5 ohm |
| SPI Clock Frequency | 5 MHz (max) |
| PWM Capability | 8-bit |
| 工作溫度範圍 | -40C to +150C |
| 封裝 | PowerSO-36 |
| 安裝類型 | Surface Mount |
| Protection Features | Overcurrent, Overtemperature, Open-Load Detection |
| RoHS 狀態 | Compliant |
| AEC-Q100 Qualified | Yes |
L9956 腳位配置
| 腳位 1 | OUT1 — Low-side output channel 1 |
| 腳位 2 | OUT2 — Low-side output channel 2 |
| 腳位 3 | OUT3 — Low-side output channel 3 |
| 腳位 4 | OUT4 — Low-side output channel 4 |
| 腳位 5 | OUT5 — Low-side output channel 5 |
| 腳位 6 | OUT6 — Low-side output channel 6 |
| 腳位 7 | OUT7 — Low-side output channel 7 |
| 腳位 8 | OUT8 — Low-side output channel 8 |
| 腳位 9 | GND — Ground |
| 腳位 10 | VCC — Logic supply voltage (5V) |
| 腳位 11 | VS — Power supply voltage (battery) |
| 腳位 12 | SCK — SPI clock input |
| 腳位 13 | SI — SPI data input |
| 腳位 14 | SO — SPI data output |
| 腳位 15 | CSN — SPI chip select (active low) |
| 腳位 16 | RSTN — Reset input (active low) |
典型應用
L9956 適用於 6 應用s: Automotive Body Control Module, Industrial Relay Replacement, LED Lighting Control, Solenoid and Valve Control, Automotive Lighting, Motor Control.
Automotive Body Control Module
The L9956 is ideal for automotive body control modules (BCMs) that manage exterior and interior lighting, door locks, and window motors. Its 8 channels can drive multiple loads simultaneously, while the SPI interface enables real-time diagnostics and control. The device's AEC-Q100 qualification ensures reliability in harsh automotive environments. With a supply voltage range of 4.5V to 28V, it can handle load dump and cold crank conditions. The built-in protection features (overcurrent, overtemperature, open-load) prevent damage to the BCM and connected loads. The PowerSO-36 package with exposed pad allows efficient heat dissipation, crucial for high-current applications. The L9956's low quiescent current in standby mode helps reduce battery drain when the vehicle is off. Overall, the L9956 simplifies BCM design by integrating multiple functions into a single device, reducing PCB area and component count.
推薦
Industrial Relay Replacement
The L9956 can replace electromechanical relays in industrial control systems, offering faster switching, longer lifespan, and built-in diagnostics. Its low-side driver configuration is suitable for switching DC loads such as solenoids, valves, and lamps. The device's 1.5A per channel output current is sufficient for many industrial loads, and the 8-bit PWM capability allows proportional control. The SPI interface enables remote monitoring and control, reducing wiring complexity. The L9956's protection features (overcurrent, overtemperature) enhance system safety, preventing damage to the driver and loads. The PowerSO-36 package is compatible with standard SMD assembly, simplifying manufacturing. Compared to relays, the L9956 offers solid-state reliability, no mechanical wear, and faster response times. This makes it ideal for applications requiring high switching frequency or precise control.
推薦
LED Lighting Control
The L9956 is well-suited for LED lighting control in automotive and industrial applications. Its 8 channels can independently drive LED strings, and the 8-bit PWM capability enables precise dimming and color control. The device's low on-resistance (0.5 ohm) minimizes power loss, improving efficiency. The SPI interface allows dynamic adjustment of brightness and fault detection (open-load, overcurrent). The L9956's wide supply voltage range (4.5V to 28V) accommodates various LED configurations. The built-in protection features prevent LED damage due to overcurrent or overtemperature. The PowerSO-36 package with exposed pad ensures adequate heat dissipation for high-power LEDs. Compared to discrete MOSFET drivers, the L9956 simplifies design by integrating control logic and protection, reducing component count and PCB area.
推薦
Solenoid and Valve Control
The L9956 is ideal for controlling solenoids and valves in industrial automation and automotive systems. Its low-side driver configuration is perfect for switching inductive loads, and the built-in freewheeling diodes clamp inductive kickback, eliminating the need for external clamping components. The device's 1.5A per channel output current is sufficient for most solenoids and valves. The SPI interface enables precise timing and diagnostics, allowing detection of open-load or short-circuit conditions. The L9956's protection features (overcurrent, overtemperature) ensure reliable operation in demanding environments. The wide supply voltage range (4.5V to 28V) makes it compatible with various power systems. The PowerSO-36 package provides good thermal performance, essential for continuous operation. Compared to discrete solutions, the L9956 reduces design complexity and improves reliability.
推薦
Automotive Lighting
The L9956 is designed for automotive lighting applications, including headlights, taillights, and interior lighting. Its 8 channels can drive multiple lamps or LED strings, and the 8-bit PWM capability enables dimming and adaptive lighting features. The device's AEC-Q100 qualification ensures reliability in automotive environments. The SPI interface allows communication with the vehicle's body control module for diagnostics and control. The L9956's protection features (overcurrent, overtemperature, open-load) prevent damage to the lighting system. The wide supply voltage range (4.5V to 28V) handles voltage fluctuations during engine start and load dump. The PowerSO-36 package with exposed pad ensures efficient heat dissipation for high-power lamps. Compared to discrete drivers, the L9956 simplifies wiring and reduces component count.
推薦
Motor Control
The L9956 can be used for controlling small DC motors in automotive and industrial applications. Its low-side driver configuration is suitable for driving motors in one direction, and the 8-bit PWM capability allows speed control. The device's 1.5A per channel output current is sufficient for small motors. The SPI interface enables precise speed control and diagnostics, such as stall detection. The L9956's protection features (overcurrent, overtemperature) prevent motor and driver damage. The wide supply voltage range (4.5V to 28V) accommodates various motor voltages. The PowerSO-36 package provides good thermal performance for continuous motor operation. Compared to discrete H-bridge drivers, the L9956 is simpler but limited to unidirectional control. For bidirectional control, two channels can be used in an H-bridge configuration.
推薦
推薦產品摘要
工程參考資料，適用於 L9956 — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | L9956XP | L9955 | L9958 | TLE6228GP | MC33882 |
|---|---|---|---|---|---|---|
| Package | PowerSO-36 | PowerSO-36 - same | PowerSO-36 - same | PowerSO-36 - same | PowerSO-36 - same | PowerSO-36 - same |
| Brand | STMicroelectronics | STMicroelectronics | STMicroelectronics | STMicroelectronics | Infineon | NXP Semiconductors |
| Number of Channels | 8 | 8 | 4 | 8 | 8 | 8 |
| Output Current per Channel | 1.5 A | 1.5 A | 1 A | 1.5 A | 1.5 A | 1.5 A |
| SPI Clock Frequency | 5 MHz | 5 MHz | 5 MHz | 5 MHz | 5 MHz | 5 MHz |
| PWM Capability | 8-bit | 8-bit | 8-bit | 8-bit | 8-bit | 8-bit |
| AEC-Q100 Qualified | Yes | Yes | Yes | Yes | Yes | Yes |
| On-Resistance (Typical) | 0.5 ohm | 0.5 ohm | 0.5 ohm | 0.5 ohm | 0.5 ohm | 0.5 ohm |
主要差異化特點
- 8 channels in a single package (對比L9955)
- Higher output current per channel (對比L9955)
- Enhanced ESD protection in L9956XP (對比L9956)
設計說明
The L9956 can dissipate significant power when driving multiple channels at high current. For example, with 8 channels at 1.5A each and a supply voltage of 12V, the total power dissipation can reach several watts. Ensure adequate PCB copper area and thermal vias to the exposed pad to keep the junction temperature below the maximum rating. Refer to the thermal impedance data in the datasheet for proper heatsinking.
Place decoupling capacitors (100nF and 10uF) close to the VCC and VS pins to filter noise and stabilize the supply. For the SPI lines, use series resistors (e.g., 33 ohm) to reduce ringing and improve signal integrity. Keep the SPI traces short and avoid routing them near high-current switching outputs to prevent crosstalk.
Ensure the logic supply (VCC) is within the specified range (4.5V to 5.5V) to avoid malfunction. The power supply (VS) must be decoupled with a bulk capacitor to handle load transients. Do not exceed the absolute maximum ratings for output current or supply voltage. When driving inductive loads, verify that the built-in freewheeling diodes are sufficient for the load's energy; otherwise, add external clamping.
合規資訊
RoHS compliant and AEC-Q100 qualified per STMicroelectronics product page. Halogen-free status not specified in available data.