Texas Instruments LP39542TL/NOPB

Overview

LP39542TL/NOPB from Texas Instruments is an advanced lighting management unit (LMU) for RGB and white LED control in handheld devices. It integrates a high-efficiency boost DC-DC converter (4.0–5.3 V, up to 400 mA), six constant-current RGB outputs (up to 40 mA/LED), and six WLED drivers (0–25 mA/LED per channel), with I²C interface, audio synchronization input, and programmable blinking sequences. It is used in cellular phone display backlights, keypad illumination, and camera flash subsystems.

For engineers reviewing the LP39542TL/NOPB datasheet, LP39542TL/NOPB pinout, LP39542TL/NOPB application, or LP39542TL/NOPB equivalent, key selection criteria include boost output voltage programmability (8-bit register), dual RGB driver sets with independent current control, integrated ambient light/temperature sensing capability via ADC inputs, and DSBGA-36 package compatibility with space-constrained mobile PCB layouts.

Technical Context

The LP39542TL/NOPB implements a magnetic boost DC/DC converter using current-programmed mode (CPM) topology with selectable switching frequencies (1/1.67/2 MHz) set by external timing resistor R_RT. Its internal oscillator governs all timing-critical functions including RGB pattern generation, fade transitions, and flash timing.

It supports four concurrent LED control modes per RGB bank: command-based pattern generation (8×16-bit programmable commands), real-time audio synchronization (ASE input), ON/OFF blinking sequences, and external PWM dimming (SYNC/PWM pin, ≤1 kHz). White LED banks operate in 4+2 or 6-channel configuration with 8-bit current adjustment per LED.

Key Specifications

Pinout & Package

LP39542TL/NOPB uses a 36-ball DSBGA package (YZR0036/YPG0036) with 0.5 mm pitch, 3.0 × 3.0 mm footprint, and 0.6–0.65 mm height. Thermal performance is characterized by θ_JA = 60°C/W under standard JEDEC conditions.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar lighting management applications.

Compared with LP55231RSBT and TPS61165DRVR, the LP39542TL/NOPB uniquely integrates RGB pattern generation, WLED backlighting, high-current flash, and audio synchronization in one DSBGA package-enabling full lighting subsystem consolidation without compromising feature depth or timing precision.

Availability

LP39542TL/NOPB is available at Aetrix Electronics and suitable for cellular phones, PDAs, MP3 players, and handheld industrial terminals requiring stable component supply, long-term lifecycle support, and guaranteed traceability.

Supply support for LP39542TL/NOPB 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 experience in mobile power and lighting solutions.

The LP39542TL/NOPB belongs to TI's Advanced Lighting Management Unit product line, designed specifically to consolidate RGB, WLED, and flash control in space- and power-constrained handheld devices while minimizing host MCU overhead.

FAQ

What is the maximum output voltage and current capability of the LP39542TL/NOPB boost converter?

The LP39542TL/NOPB boost converter delivers a programmable output voltage from 4.0 V to 5.3 V in nine discrete steps via an 8-bit register. Its maximum continuous output current is 400 mA at V_OUT = 4 V and 300 mA at V_OUT = 5 V, with internal current limiting and thermal protection ensuring safe operation under peak load conditions. The LP39542TL/NOPB uses a CPM control architecture for stable regulation across battery voltage ranges (3.0–4.5 V).

How does the LP39542TL/NOPB support audio synchronization for RGB LEDs?

The LP39542TL/NOPB features a dedicated ASE (Audio Synchronization Enable) analog input pin that accepts a 0.1–V_DDA−0.1 V signal to directly modulate RGB LED intensity and color transitions in real time. This hardware-based synchronization bypasses the need for MCU-based FFT or envelope detection, enabling responsive visual feedback aligned to music or voice without firmware latency. The LP39542TL/NOPB processes the ASE signal internally to drive R1/G1/B1 and/or R2/G2/B2 outputs based on register configuration.

Can the LP39542TL/NOPB drive both white LEDs and RGB LEDs simultaneously?

Yes, the LP39542TL/NOPB concurrently drives six white LEDs (WLED1–WLED6) and two RGB banks (R1/G1/B1 and R2/G2/B2) with independent current control. White LED channels support 0–25 mA per LED in 4+2 or 6-bank configurations for display backlighting, while RGB banks deliver up to 40 mA per channel for keypad or notification lighting. All channels operate under shared I²C control and coordinated timing, allowing synchronized effects across mixed LED types in the LP39542TL/NOPB.

What package type and dimensions does the LP39542TL/NOPB use?

The LP39542TL/NOPB is housed in a DSBGA-36 wafer-level chip-scale package measuring 3.0 mm × 3.0 mm × 0.6 mm (height) with 0.5 mm ball pitch. It carries TI's YZR0036 or YPG0036 package designation and is optimized for ultra-thin mobile designs. The package includes exposed thermal pad design and supports standard reflow profiles per JEDEC J-STD-020, with θ_JA = 60°C/W under typical PCB layout conditions.

Does the LP39542TL/NOPB support external PWM dimming for its LED outputs?

Yes, the LP39542TL/NOPB supports external PWM dimming via the SYNC/PWM pin (Pin 4D), which accepts signals up to 1 kHz. Individual control bits in the Ext. PWM Control register (07H) allow assignment of the external PWM signal to any combination of R1/G1/B1/R2/G2/B2, WLED1–WLED6, or FLASH outputs. When enabled, the external PWM overrides internal intensity settings-allowing hybrid control where the LP39542TL/NOPB handles current regulation while an external source manages timing.