Texas Instruments TPS92518PWPT

Overview

TPS92518PWPT from Texas Instruments is a dual-channel buck LED controller with SPI interface, designed for high-precision current regulation in automotive and industrial LED lighting systems. It supports 6.5 V to 42 V input, delivers independent quasi-hysteretic control per channel, enables 10,000:1 PWM dimming, and integrates high-side differential current sensing with programmable peak threshold (255 mV typ) and controlled off-time (4.1 µs typ at VLED=30 V).

For engineers reviewing the TPS92518PWPT datasheet, TPS92518PWPT pinout, TPS92518PWPT application, or TPS92518PWPT equivalent, this device is selected for adaptive matrix headlamps, color-mixing luminaires, and high-dynamic-range projector drivers requiring synchronized dual-channel analog+PWM dimming, fault reporting via SPI, and shunt-FET-compatible timing architecture.

Technical Context

The TPS92518PWPT implements a quasi-hysteretic, constant off-time (COT) control architecture where each channel independently regulates LED current using a digitally programmable peak-current comparator (8-bit DAC, 10–255 mV range) and an output-voltage-scaled off-timer (µs·V mode). Switching frequency ranges from 1 kHz to 2 MHz depending on VIN, VLED, and programmed TOFF_DAC value.

It features two fully isolated gate drivers (GATE1/GATE2), dual high-side current sense inputs (CSP1/CSN1 and CSP2/CSN2), integrated VCCx LDOs (7.5 V typ), and a dedicated SPI interface (MOSI/MISO/SCK/SSN) supporting register read/write, fault logging (over-temp, UVLO, open-load), and real-time ADC monitoring of VLED and die temperature.

Key Specifications

Pinout & Package

TPS92518PWPT is housed in a 24-pin HTSSOP package (PWP) with an exposed thermal pad connected to GND. The package supports standard reflow profiles and requires thermal vias under the pad for optimal junction-to-board conduction (RθJB = 15.7 °C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-channel LED controller applications.

Compared with TPS92518PWPT, the TPS92518HV extends input voltage capability without altering control architecture or pin compatibility, while the LM3409Q-Q1 sacrifices digital flexibility and channel count for simplicity and lower unit cost in non-synchronized designs.

Availability

TPS92518PWPT is available at Aetrix Electronics and suitable for automotive adaptive lighting, RGB color-mixing luminaires, and industrial projector light engines requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for TPS92518PWPT includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and power management technologies with decades of automotive-grade reliability validation.

The TPS92518PWPT belongs to TI's LED lighting controller product line, engineered specifically for high-performance, digitally configurable multi-channel LED drivers in safety-critical and thermally demanding environments.

FAQ

What is the maximum input voltage rating for the TPS92518PWPT?

The TPS92518PWPT has an absolute maximum input voltage rating of 44 V on the VIN pin. Its recommended operating input voltage range is 6.5 V to 42 V. Exceeding 44 V risks permanent damage; for systems with transient spikes above 42 V (e.g., automotive load dump), external clamping or selection of the TPS92518HV variant (65 V max) is required. The TPS92518PWPT datasheet specifies this limit in Section 6.1 Absolute Maximum Ratings.

Does the TPS92518PWPT support hardware PWM dimming on both channels simultaneously?

Yes, the TPS92518PWPT provides dedicated PWM1 and PWM2 inputs that directly control channel current with sub-100 ns propagation delay. Both inputs operate independently and can be driven synchronously or asynchronously. This enables true per-channel PWM dimming without SPI intervention, critical for applications like adaptive headlamps requiring microsecond-level timing alignment. The TPS92518PWPT datasheet confirms this in Section 8.3.1 and Table 5 Pin Functions.

How does the TPS92518PWPT implement constant inductor ripple across varying LED forward voltages?

The TPS92518PWPT uses a µs·V off-time architecture: its internal off-timer scales linearly with the VLEDx pin voltage, ensuring constant peak-to-peak inductor current ripple (ΔIL-PP) regardless of LED string voltage. For example, at VLED=30 V and TOFF_DAC=255, tOFF ≈ 4.1 µs; at VLED=15 V, tOFF adjusts to ~8.2 µs. This behavior is defined in Equation 6 of the TPS92518PWPT datasheet and eliminates need for loop compensation in CCM/DCM transitions.

Can the TPS92518PWPT be used without SPI configuration?

Yes - the TPS92518PWPT supports standalone operation. When EN/UV is pulled above 23.6 V, it bypasses SPI initialization and loads factory-default register values (e.g., PKTH_DAC=127, TOFF_DAC=255). All core functions - buck regulation, PWM dimming, fault protection - remain active. SPI is optional for calibration, diagnostics, and dynamic reconfiguration; the TPS92518PWPT datasheet details this in Section 5 Pin Functions and Section 8.3.1.3.

What thermal management provisions does the TPS92518PWPT include?

The TPS92518PWPT integrates thermal shutdown at 175 °C (10 °C hysteresis) and reports die temperature via SPI-accessible ADC (VTHERM register). Its HTSSOP-24 package features an exposed thermal pad tied to GND, with documented RθJB = 15.7 °C/W. Layout guidelines recommend ≥4 thermal vias under the pad and a solid ground plane. These features ensure reliable operation up to +125 °C ambient in automotive and industrial applications per the TPS92518PWPT datasheet Sections 6.4 and 11.