Texas Instruments LP5864RSMR

Overview

LP5864RSMR from Texas Instruments is a 4 × 18 LED matrix driver IC integrating 18 precision constant-current sinks and 4 high-side PMOS scan switches for driving up to 72 individual LED dots or 24 RGB pixels. It supports simultaneous 8-bit analog dimming (dot current gain) and configurable 8-/16-bit PWM dimming with >20 kHz frequency to eliminate audible noise, operating across 2.7 V–5.5 V VCC/VLED and compatible with 1.8 V/3.3 V/5 V logic. It is used in high-fidelity LED animation systems such as gaming peripherals and smart speaker status displays.

For engineers reviewing the LP5864RSMR datasheet, LP5864RSMR pinout, LP5864RSMR application, or LP5864RSMR equivalent, this page delivers verified functional identity, validated package mapping (VQFN-32), confirmed pin roles, exact dimming architecture (dual analog+PWM), and real-world selection guidance - all extracted from TI's official SNVSC52 datasheet and orderable documentation.

Technical Context

The LP5864RSMR implements time-multiplexed matrix control using four independently configurable high-side PMOS switches (SW0–SW3) and 18 current sinks (CS0–CS17), enabling full 72-dot addressing via SRAM-based frame buffering. Its dual-dimming architecture combines per-dot 8-bit analog current gain (DC register) with individually assignable 8-/16-bit PWM generators - each capable of >20 kHz operation to suppress acoustic noise.

Ghost cancellation is implemented via programmable upside deghosting (scan-line discharge) and downside deghosting (current-sink precharge), while low-brightness compensation applies per-group correction across three fixed CS groupings. Interface selection between 1-MHz I²C and 12-MHz SPI is controlled by the dedicated IFS pin, with VIO_EN supporting independent 1.8 V–5 V digital supply domain.

Key Specifications

Pinout & Package

VQFN-32 (RSM) package, 4 mm × 4 mm body size with exposed thermal pad (GND-connected). Pin pitch: 0.5 mm. RoHS-compliant, moisture sensitivity level (MSL) 2.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LP5862RSMR, LP5864RSMR provides double the scan lines and current sinks for full 72-dot coverage without changing firmware logic; compared with LP5866RKPR, it offers identical feature depth in a smaller, lower-cost 32-pin package - ideal for mid-density consumer lighting where pin count and thermal budget are constrained.

Availability

LP5864RSMR is available at Aetrix Electronics and suitable for gaming peripheral lighting, smart speaker status indication, and home appliance control panel applications requiring stable component supply, long-lifecycle support, and consistent parametric performance across production batches.

Supply support for LP5864RSMR 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 and automotive-grade qualification.

The LP586x family - including LP5864RSMR - was engineered specifically for high-fidelity, low-noise LED matrix animation in consumer electronics, emphasizing SRAM efficiency, ghost cancellation, and dual-dimming precision for premium user interfaces.

FAQ

What is the maximum number of LEDs the LP5864RSMR can drive?

The LP5864RSMR drives up to 72 individual LED dots (4 scan lines × 18 current sinks) or 24 RGB pixels. This is achieved via time-multiplexed matrix control with programmable scan line count (1–4), and all 72 positions are individually addressable through its internal SRAM frame buffer. The LP5864RSMR does not support direct 1:1 mapping beyond 72 dots without external multiplexing.

Does the LP5864RSMR support both I²C and SPI interfaces simultaneously?

No - the LP5864RSMR uses a single shared physical interface with mode selection via the IFS pin: IFS = Low configures SCL_SCLK/SDA_MOSI/ADDR0_MISO/ADDR1_SS for I²C (≤1 MHz), while IFS = High reassigns them to SPI (≤12 MHz). Both protocols use identical pin assignments but require exclusive configuration; concurrent operation is not supported.

How does the LP5864RSMR handle LED open-circuit and short-circuit faults?

The LP5864RSMR integrates per-channel LED fault detection: open detection triggers when voltage at a CS pin exceeds 0.25 V (indicating no current path), and short detection activates when voltage drops below VLED – 1 V (indicating unintended low-impedance path). These thresholds are fixed and monitored continuously during active operation, with status reported via dedicated register bits.

What is the purpose of the VSYNC pin on the LP5864RSMR?

The VSYNC pin on the LP5864RSMR accepts an external synchronization pulse to align frame updates across multiple LP5864RSMR devices in multi-chip LED systems. It is required for Display Mode 2 and Mode 3 operation, ensuring simultaneous scan-line activation and eliminating visible tearing or timing skew between adjacent panels or zones driven by separate LP5864RSMR ICs.

Can the LP5864RSMR operate with different supply voltages for VCC and VLED?

Yes - the LP5864RSMR supports independent VCC (2.7–5.5 V, powers logic and LDO) and VLED (2.7–5.5 V, powers high-side switches SW0–SW3). This separation allows optimization: e.g., VCC = 3.3 V for MCU compatibility while VLED = 5 V to maximize forward voltage headroom for high-V_f LEDs, improving efficiency and thermal margin without requiring external boost circuitry.