NXP Semiconductors PCA9959HNMP

Overview

PCA9959HNMP from NXP Semiconductors is a 24-channel SPI-controlled constant-current LED driver optimized for RGBA LED dimming and blinking, delivering up to 63 mA per channel with ±8 % absolute current accuracy at 60 mA, 6-bit (64-step) per-channel brightness control, and integrated open/short load and overtemperature detection. It operates from 2.7 V to 5.5 V and supports daisy-chained SPI communication up to 10 MHz for compact LED array control in space-constrained displays.

For engineers reviewing the PCA9959HNMP datasheet, PCA9959HNMP pinout, PCA9959HNMP application, or PCA9959HNMP equivalent, this device is selected for precise multi-color LED timing control, fault-aware lighting systems requiring real-time error reporting via EFLAG registers, and synchronized fade-in/fade-out using programmable 64-grid gradation with adjustable grid duration (2.5 μs to 1 ms).

Technical Context

The PCA9959HNMP implements a dedicated 8 MHz internal oscillator driving a 64-grid gradation state machine, where each of four assignable groups independently cycles through brightness steps defined across 64 configurable grids. Its 24 constant-current sinks are individually programmed via CHx_CFG1–CHx_CFG4 registers and support four preset current levels per channel during gradation.

LED fault detection operates during active gradation cycles-alternating open/short checks per grid (except Grid63, which performs both), with real-time status reported in six EFLAG registers (02h–07h). Thermal shutdown activates when junction temperature exceeds process limits, and error flags clear only after writing '1' to CLRERR (MODE2 bit 4) and correcting the physical fault.

Key Specifications

Pinout & Package

HVQFN40 package (5 mm × 5 mm × 0.85 mm), thermally enhanced with exposed center pad soldered to VSS. Requires connection of both VSS pins (21, 40) and thermal pad to ground for proper operation and thermal performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar constant-current LED driver applications.

Compared with TLC5940RTQR and IS31FL3728-QFLS4-TR, PCA9959HNMP uniquely combines 24-channel SPI daisy-chaining, hardware-accelerated 64-grid gradation with microsecond grid timing, and per-channel open/short detection - making it optimal for fault-critical, multi-device LED systems demanding deterministic timing and diagnostics.

Availability

PCA9959HNMP is available at Aetrix Electronics and suitable for RGB status indicators, keypad backlights, LED display modules, and fade-controlled breath lights requiring stable component supply, long-term production continuity, and guaranteed thermal performance in HVQFN40 packaging.

Supply support for PCA9959HNMP 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

NXP Semiconductors is a global semiconductor company specializing in secure connectivity solutions for automotive, industrial, and IoT applications, with leadership in interface, power management, and LED driver ICs.

The PCA9959HNMP belongs to NXP's precision LED driver product line, designed specifically for high-reliability, multi-color LED systems requiring autonomous gradation control, real-time fault monitoring, and robust thermal management in compact form factors.

FAQ

What is the maximum LED supply voltage supported by PCA9959HNMP?

The PCA9959HNMP LED outputs tolerate up to 5.5 V when in the OFF state, allowing direct connection to common 3.3 V or 5 V LED supply rails without external clamping. This specification is confirmed in Section 1 of the datasheet and applies to all 24 LEDx sink terminals regardless of current setting or gradation mode.

How does PCA9959HNMP handle LED open-circuit detection during operation?

PCA9959HNMP performs open-circuit detection during active gradation cycles-not at power-up or static states. It alternates open/short checks per grid (except Grid63, which performs both), reporting results in EFLAG0–EFLAG5 registers. Detection requires the affected channel to be ON during the tested grid; unused channels must be set OFF to avoid false errors.

Can PCA9959HNMP be used in daisy-chained SPI configurations?

Yes, PCA9959HNMP supports true daisy-chained SPI operation: SDO of one device connects to SDI of the next, with shared CS, SCLK, and OE lines. The 4-wire interface processes (16 × n)-bit frames (n = number of devices), enabling scalable control of dozens of LEDs with minimal MCU GPIO usage and deterministic timing alignment.

What is the role of the REXT pin on PCA9959HNMP?

The REXT pin (Pin 39) accepts an external resistor connected to ground to set the reference current for all 24 LED channels. The value of REXT directly determines the full-scale sink current (e.g., 63 mA), with accuracy specified as ±8 % at 60 mA. This single-point calibration eliminates per-channel resistor networks and simplifies BOM management.

Does PCA9959HNMP support synchronized LED on/off across multiple devices?

Yes, the active LOW OE (Output Enable) pin (Pin 8) provides hardware-level synchronization: asserting OE simultaneously disables all LED outputs across multiple daisy-chained PCA9959HNMP devices, eliminating timing skew between units. This feature is essential for strobe lighting, system-wide power-down, or coordinated visual effects.