Texas Instruments LP5862RSMR

Overview

LP5862RSMR from Texas Instruments is a 2 × 18 LED matrix driver IC with integrated high-side PMOS switches and 18 precision constant-current sinks, supporting up to 36 individually addressable LED dots or 12 RGB pixels via time-multiplexed scanning. It delivers 50 mA per sink at VCC ≥ 3.3 V, ±5% device-to-device and channel-to-channel current matching, and supports both 8-bit analog dimming (dot current gain) and 8-/16-bit PWM dimming with >20 kHz frequency to eliminate audible noise.

For engineers reviewing the LP5862RSMR datasheet, LP5862RSMR pinout, LP5862RSMR application, or LP5862RSMR equivalent, key selection considerations include its dual-scan matrix topology, VQFN-32 package with exposed thermal pad, I²C (up to 1 MHz) and SPI (up to 12 MHz) interface flexibility, full SRAM-based frame buffer, and integrated open/short LED detection for robust lighting control in compact consumer electronics.

Technical Context

The LP5862RSMR implements a time-multiplexed 2-line scan architecture using two integrated high-side PMOS switches (SW0/SW1) and 18 current sinks (CS0–CS17), enabling dynamic control of 36 LED positions without external row drivers. Its internal 32 MHz oscillator feeds configurable PWM generators with phase-shift capability to balance transient power and suppress ghosting.

It integrates deghosting circuitry (upside/downside), low-brightness compensation across three CS groups, and full addressable SRAM for partial or full frame updates-reducing host MCU bandwidth requirements. Logic-level compatibility spans 1.8 V to 5 V, and shutdown current is ≤2 µA.

Key Specifications

Pinout & Package

VQFN-32 (RSM) package: 4.00 mm × 4.00 mm body with exposed thermal pad; optimized for thermal performance and space-constrained PCB layouts in consumer audio and gaming peripherals.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LED matrix driver applications.

Compared with LP5861RSMR and LP5864RSMR, the LP5862RSMR uniquely balances scan-line count, pin count, and feature set for mid-density applications-offering dual-scan capability without the complexity or footprint of four-line alternatives, and greater flexibility than single-scan variants.

Availability

LP5862RSMR is available at Aetrix Electronics and suitable for keyboard backlighting, smart speaker status rings, and pro-audio channel metering requiring stable component supply, long-lifecycle assurance, and RoHS-compliant packaging.

Supply support for LP5862RSMR 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 expertise in high-reliability LED driver design for consumer and industrial markets.

The LP586x family was engineered specifically for compact, high-fidelity LED matrix applications in audio peripherals, gaming gear, and smart home interfaces-emphasizing low EMI, thermal resilience, and minimal host MCU intervention.

FAQ

What is the maximum number of LEDs the LP5862RSMR can drive?

The LP5862RSMR drives up to 36 individual LED dots using its 2 × 18 time-multiplexed matrix architecture - achieved via two integrated high-side PMOS switches (SW0/SW1) and 18 constant-current sinks (CS0–CS17). It also supports 12 RGB pixels by grouping three LEDs per position. This configuration is fixed for the LP5862RSMR and cannot be expanded beyond 36 dots without external multiplexing.

Does the LP5862RSMR support both I²C and SPI interfaces simultaneously?

No, the LP5862RSMR uses a hardware-selectable interface: the IFS pin determines mode - low for I²C (SCL/SDA), high for SPI (SCLK/MOSI/MISO/SS). Both protocols share physical pins but operate exclusively. I²C supports up to 1 MHz (fast-mode plus), while SPI supports up to 12 MHz, allowing designers to choose based on host MCU capability and data throughput needs.

How does the LP5862RSMR handle LED open-circuit and short-circuit faults?

The LP5862RSMR implements per-channel LED open and short detection using internal comparators. Open detection triggers when sink voltage exceeds 0.25 V; short detection activates when voltage drops below (VLED − 1 V). Fault status is reported via dedicated registers, enabling firmware to isolate failed LEDs without external sensing components - a core reliability feature of the LP5862RSMR.

What thermal management features does the LP5862RSMR include?

The LP5862RSMR integrates thermal shutdown at 150 °C with 15 °C hysteresis, and its VQFN-32 (RSM) package includes an exposed thermal pad for direct PCB copper connection. Thermal resistance is RθJA = 32.9 °C/W (junction-to-ambient) and RθJB = 12.3 °C/W (junction-to-board), enabling reliable operation at 85 °C ambient when properly heatsinked - critical for sealed enclosures in smart speakers and appliances.

Can the LP5862RSMR achieve flicker-free PWM dimming at low brightness levels?

Yes, the LP5862RSMR supports flicker-free dimming down to very low brightness via three complementary techniques: (1) 125 kHz PWM frequency (beyond human perception), (2) programmable low-brightness compensation across three CS groups, and (3) phase-shifted PWM timing to distribute current transients. These features are implemented in silicon and require no host MCU intervention - a defining capability of the LP5862RSMR.