Texas Instruments LP5868TRKPR

Overview

LP5868TRKPR from Texas Instruments is an 8 × 18 high-current LED matrix driver IC with 18 constant current sinks and 8 high-side PMOS scan switches, supporting up to 144 individually addressable LED dots. It delivers 100 mA per sink at VCC ≥ 3.3 V, ±5% device-to-device and channel-to-channel current accuracy, and supports both 8-bit/16-bit PWM (62.5–125 kHz) and 8-bit analog dimming for RGB keyboard backlighting and smart appliance indicators.

For engineers reviewing the LP5868TRKPR datasheet, LP5868TRKPR pinout, LP5868TRKPR application, or LP5868TRKPR equivalent, key selection criteria include its VQFN-40 (5.0 mm × 5.0 mm) package, dual I²C (1 MHz max) / SPI (12 MHz max) interface, integrated open/short detection, de-ghosting circuitry, and support for audible-noise-free PWM dimming across individual, group, and global control domains.

Technical Context

The LP5868TRKPR implements a time-multiplexed 8-line × 18-sink architecture with configurable scan line count (6–8 lines), phase-shifted PWM generation to balance transient power, and full SRAM-based frame buffering to minimize host data traffic. Its internal 32 MHz oscillator feeds programmable PWM generators with selectable 62.5 kHz or 125 kHz base frequencies.

It integrates dedicated analog dimming paths - global 3-bit Maximum Current (MC), three 7-bit Color Current (CC) groups, and per-dot 8-bit Dot Current (DC) - alongside digital control of high-side PMOS switches (RSW = 310 mΩ at VLED = 5 V, ISW = 200 mA) and low-saturation current sinks (VSAT = 0.7 V at 100 mA, VCC ≥ 3.3 V).

Key Specifications

Pinout & Package

RKP package: 40-pin VQFN with 5.00 mm × 5.00 mm body and exposed thermal pad (connected to AGND). Pin count and layout match LP5866TRKPR/LP5860TRKPR for hardware compatibility within the LP586x family.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LP5866TRKPR and LP5860TRKPR, the LP5868TRKPR provides the optimal balance of dot density (144), thermal efficiency (RθJB = 12.0 °C/W), and feature parity - making it the default choice for mid-size RGB UIs where scalability beyond 108 dots is needed but 198 dots would over-specify cost and power.

Availability

LP5868TRKPR is available at Aetrix Electronics and suitable for smart home appliance indicators, RGB mechanical keyboard backlighting, and outdoor keypad backlighting requiring stable component supply across production lifecycles.

Supply support for LP5868TRKPR 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 high-reliability power management solutions.

The LP5868TRKPR belongs to TI's LP586x LED matrix driver family, engineered for high-density, low-noise, and thermally efficient LED control in consumer and industrial human-machine interfaces.

FAQ

What is the maximum LED dot count supported by the LP5868TRKPR?

The LP5868TRKPR supports up to 144 LED dots using its 8 high-side scan switches and 18 constant current sinks in an 8 × 18 matrix configuration. This is achieved through time-multiplexed scanning, and the device can also drive 48 RGB pixels. The LP5868TRKPR does not support configurations exceeding 8 scan lines - unlike the LP5860TRKPR (11 lines) or LP5866TRKPR (6 lines) - and its 144-dot capability is fixed per datasheet specification.

Does the LP5868TRKPR support both I²C and SPI interfaces simultaneously?

No, the LP5868TRKPR uses a single shared physical pin set for serial communication, with interface mode selected by the IFS pin voltage level: IFS = Low configures I²C (SCL_SCLK, SDA_MOSI, ADDR0_MISO, ADDR1_SS), while IFS = High configures SPI (SCL_SCLK as SCLK, SDA_MOSI as MOSI, ADDR0_MISO as MISO, ADDR1_SS as SS). The LP5868TRKPR does not support concurrent or automatic switching between protocols - the mode must be hardwired at power-up.

How does the LP5868TRKPR handle LED open-circuit and short-circuit faults?

The LP5868TRKPR integrates per-channel open- and short-detection circuitry with fixed thresholds: VLOD_TH = 0.25 V for open detection and VLSD_TH = VLED – 1 V for short detection. When triggered, these flags are latched in dedicated status registers and can generate interrupt signals via GPIO or be polled over I²C/SPI. The LP5868TRKPR does not auto-correct faults but provides deterministic, register-accessible fault reporting for system-level diagnostics and recovery.

What thermal considerations apply to the LP5868TRKPR in continuous 100 mA operation?

In continuous 100 mA operation across all 18 sinks, the LP5868TRKPR dissipates significant power - especially at high VSAT (0.7 V typical). With RθJB = 12.0 °C/W, junction temperature rise above board temperature is ~150 °C at full load, approaching the 150 °C thermal shutdown threshold. Therefore, the LP5868TRKPR requires a robust PCB layout: the exposed thermal pad must be soldered to a solid AGND plane with ≥4 thermal vias, and ambient temperature must stay ≤85 °C. Derating is recommended for sustained 100 mA use.

Can the LP5868TRKPR achieve true 16-bit PWM dimming per LED dot?

Yes, the LP5868TRKPR supports true 16-bit PWM resolution per LED dot via its configurable PWM generator - selectable through the 'PWM_Fre' bit in the Dev_initial register. At the 16-bit setting, the effective PWM frequency drops to 62.5 kHz (vs. 125 kHz at 8-bit), maintaining >20 kHz to avoid audible noise. This 16-bit mode is implemented entirely in hardware and does not require host processor interpolation or frame doubling - the LP5868TRKPR generates the full 65,536-step duty cycle internally.