L9942-TR - Automotive Dual-Channel Low-Side Driver | STMicroelectronics
MPN: L9942-TR β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.85 | $2.85 |
| 10 | $2.56 | $25.60 |
| 100 | $2.28 | $228.00 |
| 500 | $2.05 | $1,025.00 |
| 1,000 | $1.82 | $1,820.00 |
Drop-in alternatives for L9942-TR β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
L9942
β Drop-Inβ 99,999 In Stock
$1.82 / Unit
View Datasheet βL9945
β‘ Same Packageπ Reference alternative (not in catalog)
TLE6228GP
β Drop-Inπ Reference alternative (not in catalog)
L9942-TR Maximum Ratings & Electrical Characteristics
| Number of Channels | 2 |
| Output Type | Low-Side |
| Supply Voltage Range | 4.5 V to 40 V |
| Output Current per Channel | 1.5 A |
| Control Interface | SPI (16-bit) |
| SPI Clock Frequency | 5 MHz |
| Quiescent Current | 50 uA (standby) |
| Operating Temperature Range | -40C to +150C |
| Package | PowerSO-20 |
| Mounting Type | Surface Mount |
| Protection Features | Overcurrent, Overtemperature, Short-Circuit |
| Diagnostics | SPI fault reporting |
| RoHS Status | Compliant |
| AEC-Q100 | Qualified |
| Technology | BCD (Bipolar-CMOS-DMOS) |
L9942-TR Pin Configuration
| Pin 1 | OUT1 β Output channel 1 |
| Pin 2 | OUT1 β Output channel 1 (duplicate) |
| Pin 3 | GND β Ground |
| Pin 4 | GND β Ground (duplicate) |
| Pin 5 | VCC β Supply voltage |
| Pin 6 | VCC β Supply voltage (duplicate) |
| Pin 7 | SCK β SPI clock |
| Pin 8 | SDI β SPI data input |
| Pin 9 | SDO β SPI data output |
| Pin 10 | CS β Chip select |
| Pin 11 | OUT2 β Output channel 2 |
| Pin 12 | OUT2 β Output channel 2 (duplicate) |
| Pin 13 | GND β Ground |
| Pin 14 | GND β Ground (duplicate) |
| Pin 15 | VCC β Supply voltage |
| Pin 16 | VCC β Supply voltage (duplicate) |
| Pin 17 | NC β Not connected |
| Pin 18 | NC β Not connected |
| Pin 19 | NC β Not connected |
| Pin 20 | NC β Not connected |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this component. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
L9942-TR is suitable for 6 applications: Automotive Body Control Module, Industrial PLC Output Module, Automotive LED Lighting, Relay Replacement in Smart Home, Industrial Valve Control, Automotive Wiper Control.
Automotive Body Control Module
The L9942-TR is ideal for automotive body control modules (BCMs) where it drives exterior lights, wipers, and relays. Its wide supply voltage range (4.5V to 40V) accommodates load dump transients, and the SPI interface enables diagnostics for fault detection. The dual-channel configuration allows independent control of two loads, reducing component count. The device's AEC-Q100 qualification ensures reliability in harsh automotive environments. In a typical BCM, the L9942-TR is placed between the microcontroller and the load, with the SPI lines connected to the MCU's SPI peripheral. The output channels are connected to the loads via a connector, and the VCC pin is supplied from the vehicle's battery through a protection diode. The device's overcurrent and overtemperature protection prevent damage to the PCB and loads. The low quiescent current of 50uA minimizes battery drain when the vehicle is off, which is critical for meeting standby current regulations. The SPI interface allows the MCU to read fault status and configure the device, enabling predictive maintenance and reducing warranty costs.
Recommended
Industrial PLC Output Module
In industrial PLCs, the L9942-TR drives solenoids and valves in output modules. Its 1.5A per channel output is sufficient for small solenoids, and the SPI interface allows the PLC to monitor load status. The wide operating temperature range (-40C to +150C) ensures operation in factory environments. The device's short-circuit protection prevents damage to the PLC backplane. In a typical PLC output module, the L9942-TR is connected to the PLC's backplane bus via SPI, and the output channels are connected to field devices through a terminal block. The VCC pin is supplied from the PLC's 24V power supply, and the GND pin is connected to the common ground. The device's diagnostic features allow the PLC to detect open-load and short-circuit conditions, improving system reliability. The PowerSO-20 package with exposed pad provides good thermal performance, allowing the device to dissipate heat from continuous operation. The SPI interface supports daisy-chaining, enabling multiple output modules to be controlled with a single SPI bus, reducing wiring complexity.
Recommended
Automotive LED Lighting
The L9942-TR is used in automotive LED lighting systems for controlling LED arrays. Its current-sensing capability enables precise brightness control, and the SPI interface allows for dynamic lighting effects. The device's wide supply voltage range supports both 12V and 24V systems. In a typical LED lighting application, the L9942-TR is placed between the LED driver and the LED array, with the output channels connected to the LEDs through current-limiting resistors. The SPI interface is used to set the brightness level and read fault status. The device's overcurrent protection prevents damage to the LEDs in case of a short circuit. The low quiescent current is beneficial for daytime running lights that remain on for extended periods. The PowerSO-20 package provides adequate thermal dissipation for the power dissipated in the driver. The device's AEC-Q100 qualification ensures reliability in automotive lighting applications.
Recommended
Relay Replacement in Smart Home
The L9942-TR can replace electromechanical relays in smart home systems, providing solid-state switching with diagnostics. Its low-side driver configuration is suitable for controlling AC loads via a relay or directly driving DC loads. The SPI interface allows integration with home automation hubs. In a smart home application, the L9942-TR is used to control lighting, fans, and other appliances. The device's output channels are connected to the loads, and the SPI interface is connected to a microcontroller or Wi-Fi module. The device's protection features prevent damage from overloads, and the diagnostic capabilities allow remote monitoring of load status. The wide supply voltage range (4.5V to 40V) makes it compatible with various power supplies. The low quiescent current is beneficial for battery-powered smart home devices. The PowerSO-20 package is suitable for PCB mounting in compact smart home modules.
Recommended
Industrial Valve Control
The L9942-TR is used in industrial valve control systems to drive solenoid valves. Its 1.5A output current is sufficient for most solenoid valves, and the SPI interface provides diagnostics for valve position and health. The device's wide operating temperature range ensures reliable operation in harsh industrial environments. In a typical valve control system, the L9942-TR is placed between the PLC and the solenoid valve, with the output channel connected to the valve coil. The SPI interface is used to control the valve and read fault status. The device's overcurrent protection prevents damage to the valve coil in case of a short circuit. The low quiescent current is beneficial for battery-powered valve controllers. The PowerSO-20 package provides good thermal performance for continuous operation. The device's AEC-Q100 qualification, while intended for automotive, also ensures high reliability in industrial applications.
Recommended
Automotive Wiper Control
The L9942-TR is used in automotive wiper control systems to drive the wiper motor. Its dual-channel configuration allows for controlling both the wiper motor and the washer pump. The SPI interface enables diagnostics for wiper position and motor health. The device's wide supply voltage range (4.5V to 40V) accommodates the voltage fluctuations in automotive electrical systems. In a typical wiper control system, the L9942-TR is placed between the body control module and the wiper motor, with the output channels connected to the motor and pump. The SPI interface is used to control the wiper speed and read fault status. The device's overcurrent protection prevents damage to the motor in case of a stall. The low quiescent current is beneficial for reducing battery drain when the wipers are off. The PowerSO-20 package provides adequate thermal dissipation for the motor drive current.
Recommended
Recommended Products Summary
Engineering reference data for L9942-TR β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | L9942 | L9945 | TLE6228GP |
|---|---|---|---|---|
| Package | PowerSO-20 | PowerSO-20 - same | PowerSO-20 - same | PowerSO-20 - same |
| Brand | STMicroelectronics | STMicroelectronics | STMicroelectronics | Infineon |
| Number of Channels | 2 | 2 | 4 | 2 |
| Output Current per Channel | 1.5 A | 1.5 A | 1 A | 1.5 A |
| Supply Voltage Range | 4.5V to 40V | 4.5V to 40V | 4.5V to 40V | 4.5V to 40V |
| SPI Interface | Yes (16-bit) | Yes (16-bit) | Yes (16-bit) | Yes (16-bit) |
| Quiescent Current | 50 uA | 50 uA | 60 uA | 55 uA |
| AEC-Q100 Qualified | Yes | Yes | Yes | Yes |
Key Differentiators
- Dual-channel low-side driver with SPI diagnostics (vs TLE6228GP)
- Wide supply voltage range (4.5V to 40V) (vs L9945)
- Low quiescent current of 50uA (vs L9945)
Design Notes
The L9942-TR in PowerSO-20 package has an exposed pad for thermal dissipation. Ensure the PCB has a thermal pad with multiple vias to the ground plane to keep the junction temperature below 150C. For continuous operation at 1.5A per channel, calculate power dissipation as P = I^2 * RDS(on) and size the copper area accordingly.
Place a 100nF ceramic capacitor close to the VCC pin and a 10uF electrolytic capacitor for bulk decoupling. Keep SPI lines short and shielded to avoid noise. The exposed pad should be soldered to the PCB ground plane for optimal thermal and electrical performance.
Do not exceed the absolute maximum supply voltage of 40V. Ensure the SPI lines are properly terminated to avoid ringing. The device's diagnostic features should be used to detect open-load and short-circuit conditions. Avoid driving inductive loads without a flyback diode to prevent voltage spikes.
Compliance Information
RoHS compliant and AEC-Q100 qualified per STMicroelectronics product page.
