NXP Semiconductors PCA9634PW,112

Overview

PCA9634PW,112 from NXP Semiconductors is an 8-channel I²C-bus LED driver optimized for RGBA color mixing, featuring independent 256-step (8-bit) individual PWM control at 97 kHz and a programmable group PWM controller (24 Hz to 10.73 s blink period, 0–99.6% duty cycle). It supports totem-pole (25 mA sink / 10 mA source) or open-drain (25 mA sink) output configurations and operates from 2.3 V to 5.5 V with 5.5 V-tolerant inputs. Used in keypad backlights, status indicators, and RGB displays.

For engineers reviewing the PCA9634PW,112 datasheet, PCA9634PW,112 pinout, PCA9634PW,112 application, or PCA9634PW,112 equivalent, key selection criteria include I²C Fast-mode Plus (1 MHz) compatibility, hardware address scalability (up to 126 devices), software-reset capability, OE-driven hardware dimming/blinking synchronization, and dual-layer PWM architecture enabling per-LED brightness + global blink/dim control.

Technical Context

The PCA9634PW,112 integrates a 25 MHz internal oscillator (no external components required), noise-filtered SDA/SCL inputs, and edge-rate-controlled outputs to ensure robust I²C communication on high-capacitance buses up to 4000 pF. Its register map includes dedicated PWM0–PWM7 (individual brightness), GRPPWM/GRPFREQ (group control), and LEDOUT0/LEDOUT1 (output state selection).

Control logic supports Auto-Increment modes (AI[2:0]) for sequential register access-enabling efficient bulk updates of brightness or group settings-and allows output state changes on either ACK or STOP command (default: STOP), ensuring synchronized multi-device updates. The MODE1/MODE2 registers configure sleep mode, subaddress enablement, output inversion, and totem-pole/open-drain selection.

Key Specifications

Pinout & Package

TSSOP20 package (SOT360-1), 4.4 mm body width, 20-pin surface-mount with exposed thermal pad (HVQFN20 variant only; TSSOP20 has no exposed pad).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLC59116IPWPR and IS31FL3728-QFLS4-TR, the PCA9634PW,112 uniquely combines scalable I²C addressing (126 devices), hardware blink/dim separation, and OE-synchronized hardware control-making it optimal for distributed, multi-node LED systems requiring deterministic timing and minimal host intervention.

Availability

PCA9634PW,112 is available at Aetrix Electronics and suitable for RGB status indicators, keypad backlights, LED display segments, and system status panels requiring stable component supply, long-term lifecycle support, and guaranteed traceability.

Supply support for PCA9634PW,112 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 leader focused on secure connectivity solutions for automotive, industrial, and IoT applications, with deep expertise in mixed-signal ICs and embedded processing.

The PCA9634PW,112 belongs to NXP's LED driver product line designed specifically for energy-efficient, color-accurate, and scalable lighting control in space-constrained human-interface applications.

FAQ

What is the maximum I²C bus speed supported by the PCA9634PW,112?

The PCA9634PW,112 supports Fast-mode Plus (Fm+) I²C operation up to 1 MHz, with enhanced SDA drive capability (30 mA) to maintain signal integrity on buses with up to 4000 pF total capacitance. This enables faster register writes and reduced command latency compared to standard 400 kHz I²C devices-critical for real-time LED animation updates in the PCA9634PW,112.

How does the PCA9634PW,112 handle simultaneous control of multiple devices on one I²C bus?

The PCA9634PW,112 uses seven hardware address pins (A0–A6) to assign unique 7-bit slave addresses, supporting up to 126 devices on a single bus. Additionally, its software-programmable All Call and three Sub Call addresses allow grouped commands-e.g., turning all red LEDs on across multiple PCA9634PW,112 units with one I²C write-without address conflicts or bus contention.

Can the PCA9634PW,112 drive LEDs directly without external components?

Yes-the PCA9634PW,112 can directly drive standard LEDs with up to 25 mA per channel at 5 V using its totem-pole or open-drain outputs. No external current-setting resistors or transistors are needed for basic operation. For higher-current or high-voltage LEDs, external drivers may be added-but the PCA9634PW,112 retains full PWM control authority over those stages via its output logic states.

What is the function of the OE (Output Enable) pin on the PCA9634PW,112?

The active-low OE pin on the PCA9634PW,112 provides asynchronous hardware control over all eight LED outputs. When pulled HIGH, outputs enter a user-defined state (logic HIGH, LOW, or high-impedance) per MODE2 register settings-enabling synchronized blinking or dimming across multiple PCA9634PW,112 devices using a single external clock, independent of I²C traffic or register updates.

Does the PCA9634PW,112 support both individual LED brightness and global blinking simultaneously?

Yes-the PCA9634PW,112 implements dual-layer PWM control: each LED channel (LED0–LED7) has its own 97 kHz, 256-step individual PWM register (PWM0–PWM7), while the GRPPWM and GRPFREQ registers define a separate group-level blink or dim waveform (24 Hz to 10.73 s period). When configured as "individual + group" (LDRx = 11), both layers combine multiplicatively-allowing PCA9634PW,112 to produce complex, synchronized lighting effects with minimal host overhead.