PCA9685PW - 16-Channel 12-bit PWM I2C LED Controller | NXP TSSOP-28
Teilenummer: PCA9685PW ✓ Aktiv| Menge | Stückpreis | Gesamt |
|---|---|---|
| 1 | $2.95 | $2,95 |
| 10 | $2.66 | $26,60 |
| 100 | $2.36 | $236,00 |
| 500 | $2.13 | $1.065,00 |
| 1.000 | $1.89 | $1.890,00 |
PCA9685PW Übersicht
An LED driver is an integrated circuit that switches current through light-emitting diodes at controlled duty cycles and frequencies, allowing microcontrollers to drive many more LEDs than their limited GPIO pins can support directly. The PCA9685 belongs to the LED driver / PWM controller product family within the display driver hierarchy, which sits inside power management and lighting sub-systems. Compared to discrete MOSFETs driven by GPIO bit-banging, a dedicated LED controller IC delivers programmable frequency, smooth 12-bit dimming, hardware current sinking, and synchronized multi-channel phase shifting - critical for avoiding audible flicker and for removing the MCU's software timing burden.
Key features include six hardware-selectable I2C addresses, a 1 MHz Fm+ capable SCL clock, programmable open-drain totem-pole output structure with 25 mA continuous sink, per-output 12-bit duty cycle plus 4-bit group Blink/Blink-at-fixed-frequency mode, and a 40 mA active-low Output Enable (OE) input for synchronized dimming via external PWM. The internal 25 MHz oscillator provides the time base and supports the wide 24 Hz - 1526 Hz PWM range with sub-percent duty cycle resolution.
The PCA9685PW architecture combines an I2C slave decoder, a frequency prescaler, and 16 independent 12-bit PWM latches, all driven by a single on-chip 25 MHz RC oscillator. Outputs can be configured as totem-pole (push-pull) or open-drain, providing flexibility to drive both LED cathodes to GND and LED anodes to V+. The OE pin enables global phase-shifted PWM dimming - critical when multiple PCA9685PW ICs must be synchronized to a common refresh rate for large LED matrices.
Typical applications include LCD TV/monitor RGBA LED backlighting, RGB LED strip driving, servo motor control via PWM (hobby robotics), LED matrix displays, and PC case lighting. Designers choose the PCA9685PW when they need more than the 4-6 PWM channels a typical MCU offers, require 12-bit dimming depth, or must chain multiple drivers on one I2C bus.
When designing with this device, place the 220 nF bypass capacitor on VDD and the 1 uF + 2.2 uF bulk capacitors on V+ as close as possible to the pins, and keep the SDA/SCL traces short. The OE pin must be tied HIGH when not used; leaving it floating can cause undefined output behavior.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet, providing a faster comparison surface for engineers evaluating LED controllers for backlight or robotics designs.
Drop-in-Alternativen für PCA9685PW – gleiches Gehäuse, Pin-kompatibel. Bauteile mit anderem Gehäuse, die eine PCB-Überarbeitung erfordern, sind ausgeschlossen.
Varianten dieser Serie
Modelle derselben Serie, die drop-in-kompatibel sind mit PCA9685PW (gleiche Bauform und Footprint) – abweichend in PWM Resolution, Package, Interface, Output Enable Pin (OE), PWM Frequency Range.
Schnellvergleichstool – Wählen Sie Alternativbauteile für den Direktvergleich:
PCA9685PW,118
✅ Drop-In✓ Auf Lager
$1.99 / Stück
Datenblatt ansehen →PCA9685PW,112
✅ Drop-In✓ Auf Lager
$1.78 / Stück
Datenblatt ansehen →PCA9685PW/Q900,118
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
PCA9685PW Grenzwerte & elektrische Eigenschaften
| Product Type | I2C-bus controlled 16-channel LED PWM controller |
| Anzahl der Ausgänge | 16 |
| PWM Resolution | 12-bit (4096 steps per channel) |
| PWM Frequency Range | 24 Hz to 1526 Hz (typical, programmable) |
| Output Current (per channel) | 25 mA (sink) |
| Output Structure | Open-drain or totem-pole (programmable) |
| I2C Interface | Fast-Mode Plus (Fm+) up to 1 MHz |
| I2C Address Pins | 6 hardware-selectable (up to 62 devices per bus) |
| Supply Voltage VDD | 2.3 V to 5.5 V |
| Internal Oscillator | 25 MHz |
| Betriebstemperatur | -40 C to +85 C |
| Gehäuse | TSSOP-28 (SOT361-1) |
| Montageart | Surface Mount |
| Output Enable Pin (OE) | Yes, active-low, synchronized dimming |
| RoHS-Status | Compliant |
PCA9685PW Pin-Konfiguration
| Pin 1 | A0 — I2C slave address bit 0 (tie to VDD or GND) |
| Pin 2 | A1 — I2C slave address bit 1 |
| Pin 3 | A2 — I2C slave address bit 2 |
| Pin 4 | A3 — I2C slave address bit 3 |
| Pin 5 | A4 — I2C slave address bit 4 |
| Pin 6 | A5 — I2C slave address bit 5 |
| Pin 7 | OE — Output Enable, active-low (tie HIGH if unused) |
| Pin 8 | GND — Ground |
| Pin 9 | LED0 — PWM output 0 (open-drain or totem-pole) |
| Pin 10 | LED1 — PWM output 1 |
| Pin 11 | LED2 — PWM output 2 |
| Pin 12 | LED3 — PWM output 3 |
| Pin 13 | LED4 — PWM output 4 |
| Pin 14 | LED5 — PWM output 5 |
| Pin 15 | LED6 — PWM output 6 |
| Pin 16 | LED7 — PWM output 7 |
| Pin 17 | LED8 — PWM output 8 |
| Pin 18 | LED9 — PWM output 9 |
| Pin 19 | LED10 — PWM output 10 |
| Pin 20 | LED11 — PWM output 11 |
| Pin 21 | LED12 — PWM output 12 |
| Pin 22 | LED13 — PWM output 13 |
| Pin 23 | LED14 — PWM output 14 |
| Pin 24 | LED15 — PWM output 15 |
| Pin 25 | V+ — LED supply voltage (load side) |
| Pin 26 | VDD — Logic supply voltage 2.3 V to 5.5 V |
| Pin 27 | SCL — I2C serial clock (Fm+ 1 MHz capable) |
| Pin 28 | SDA — I2C serial data |
Typische Anwendungen
PCA9685PW ist geeignet für 7 Anwendungs: LCD TV / Monitor RGBA Backlighting, RGB LED Strip Driver, Hobby Servo / Robotics PWM, LED Matrix Display Driver, PC Case and Modding Lighting, Servo Motor Control for Industrial Automation, Education and Maker Electronics.
LCD TV / Monitor RGBA Backlighting
The NXP PCA9685PW drives Red/Green/Blue/Amber LED backlight strings behind LCD panels using its 16 individually controllable 12-bit PWM channels, where each channel produces 4096 brightness steps so color mixing stays smooth. Placing the IC between the LED anode rail V+ and the LED string cathodes, the 25 mA per-channel sink rating handles single bias-indicator or low-current edge strings directly, while external MOSFETs extend the design to full-area backlight arrays. The 1 MHz Fm+ I2C lets the timing controller poll backlight status without taxing its timers, and the synchronized OE pin enables global dimming from an external PWM source synchronized to the panel refresh rate. Compared with a discrete-MOSFET design, the PCA9685PW removes the BOM cost and software overhead of bit-banging 16 PWMs while keeping EMI modest thanks to the programmable 24 Hz-1526 Hz range.
Empfohlen
RGB LED Strip Driver
The NXP PCA9685PW controls 5 meters of 12 V WS281x-style analog RGB LED strips where each color channel is switched via a low-side MOSFET driven by the PCA9685PW output. Each of the 16 channels provides 12-bit (4096 step) brightness resolution and a programmable 24 Hz-1526 Hz PWM frequency, allowing the strip to dim smoothly without audible coil whine on the MOSFET gates. The I2C interface (1 MHz Fast-Mode Plus) supports daisy-chaining up to 62 PCA9685PW boards for very large installations, and the six hardware address pins let you assign discrete zones (window, ceiling, stairs) from the same microcontroller. In practice the design outperforms software bit-banging because the PCA9685PW keeps timing consistent even when the host CPU is busy running other tasks, and it requires only two microcontroller pins instead of 16 GPIO pins.
Empfohlen
Hobby Servo / Robotics PWM
Hobby servos and small DC motors accept a 50 Hz PWM signal with pulse widths between 1 ms and 2 ms; the NXP PCA9685PW provides exactly that, with 16 outputs from a single TSSOP-28 chip programmed over I2C. Setting the prescaler to 200 yields a 50 Hz refresh rate, and the 12-bit duty cycle resolution gives sub-microsecond pulse precision beyond the resolution of most analog servos. Using one PCA9685PW per 16-servo leg, a hexapod robot needs only four chips behind a single I2C bus, dramatically reducing wire count versus a per-joint microcontroller architecture. Each output also supports 25 mA sink, sufficient to drive the optocoupler or gate driver of a brushed DC motor controller, making the PCA9685PW a flexible hub for educational robotics.
Empfohlen
LED Matrix Display Driver
The NXP PCA9685PW multiplexes a 16x16 or larger LED matrix by sinking each row or column independently while the opposite rails are driven by external high-side shift registers, providing consistent brightness across all 256 LEDs. The 12-bit PWM resolution prevents visible duty-cycle steps when high-brightness LEDs are PWM-dimmed for color balance, and the global OE input allows matrix blanking during row-switching transitions to eliminate ghosting. A single PCA9685PW at 1 MHz I2C yields zero wait states for the host, with up to 62 chips cascading for stadium-sized panels. Compared to using 16 dedicated PWM timers on an MCU, the PCA9685PW reduces firmware complexity and leaves the host free for graphics rendering.
Empfohlen
PC Case and Modding Lighting
The NXP PCA9685PW is widely used to drive WS2812-style and analog RGB LED fans, strips, and individual LEDs inside a desktop PC, where 16 channels cover an entire build from one I2C address. The TSSOP-28 package is small enough to fit on a 25 mm x 25 mm daughter board, and the 25 mA per-channel sink rating directly drives status LEDs or the gate of a logic-level MOSFET for higher-current loads. Six address pins let builders multiplex up to 62 controllers off the motherboard I2C bus for full custom PCBs. Compared to USB-controlled LED controllers, the I2C PCA9685PW avoids USB enumeration latency and integrates cleanly with motherboard fan/LED headers.
Empfohlen
Servo Motor Control for Industrial Automation
The NXP PCA9685PW provides deterministic 16-channel PWM generation for industrial servo and stepper driver boards where cycle-accurate timing matters more than full motion-controller ICs. Each output is programmable in 12-bit duty-cycle increments with frequencies up to 1526 Hz, and the OE pin synchronizes all channels to an external controller pulse for closed-loop motion systems. The TSSOP-28 industrial-grade package (operating from -40 C to +85 C) tolerates factory-floor temperatures, and 1 MHz Fm+ I2C keeps response latency under 1 ms. Compared with discrete 555-timer circuits or counter-timer ICs, the PCA9685PW reduces board area and gives software-controlled timing profiles.
Empfohlen
Education and Maker Electronics
The NXP PCA9685PW appears on countless Adafruit, SparkFun, and Pololu breakout boards where it provides plug-and-play 16-channel PWM for Arduino, Raspberry Pi, and Micro:bit classrooms. Each channel is 12-bit and individually addressable over a simple I2C command set (MODE1, MODE2, LEDx_ON_L, LEDx_ON_H, LEDx_OFF_L, LEDx_OFF_H), making it ideal for teaching register-level programming. The TSSOP-28 footprint allows hand-soldering by advanced students while remaining production-friendly for kit volumes. Compared with writing custom PWM in code, students learn real I2C device-control patterns that generalize to other industrial-grade LED drivers.
Empfohlen
Zusammenfassung der empfohlenen Produkte
Technische Referenzdaten für PCA9685PW – Vergleich, Designhinweise und Compliance-Informationen.
Auswahlhilfe
Vergleich mit Alternativen
| Parameter | Dieses Produkt | PCA9685PW,118 | PCA9685PW,112 | PCA9685PW/Q900,118 |
|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | TSSOP-28 | TSSOP-28 | TSSOP-28 | TSSOP-28 |
| Number of PWM Outputs | 16 | 16 | 16 | 16 |
| PWM Resolution | 12-bit (4096 steps) | 12-bit | 12-bit | 12-bit |
| Output Current per Channel | 25 mA | 25 mA | 25 mA | 25 mA |
| I2C Interface Speed | 1 MHz Fm+ | 1 MHz Fm+ | 1 MHz Fm+ | 1 MHz Fm+ |
| Automotive Grade (AEC-Q100) | No | No | No | Yes |
| Carrier Packaging | Tube (default) | Tape & Reel (13 inch) | Tray | Tape & Reel (13 inch) |
| Unit Price (qty 1, USD as of 2026-10-14) | $2.95 | $2.95 | $2.95 | $3.45 |
Wichtigste Unterscheidungsmerkmale
- Automotive-grade drop-in option in same footprint (vs. PCA9685PW/Q900,118)
- Volume-production-ready tape-and-reel variant (vs. PCA9685PW,118)
- Three footprint-compatible NXP variants reduce sourcing risk (vs. Generic TSSOP-28 LED drivers)
Designhinweise
Estimated: the PCA9685PW draws VDD logic current (typ. 7.5 mA, this device) plus 25 mA per active LED output. At VIN=5 V with all 16 outputs active at 25 mA each, total draw is ~407 mA + 7.5 mA logic. Use a 1 uF ceramic bypass on VDD and a 2.2 uF bulk capacitor on V+ placed within 5 mm of the pins to prevent output-stage voltage drop during PWM transitions.
Keep SDA and SCL traces short (under 50 mm) and avoid routing near switching nodes. Route 4.7 kohm pull-up resistors to VDD (not V+) to ensure clean logic levels during LED current spikes. Place the OE pin directly to VDD via a 100 kohm pull-up if the pin is unused; a floating OE pin can cause undefined dimming behavior.
The 6 I2C address bits A0-A5 are sampled only at reset, so changing them mid-run will not change the active I2C address without a software reset (write 0x06 to MODE1). The 25 mA per-channel rating is a sink current spec; outputs cannot source significant current - high-side drivers or LED anode switching require external P-MOSFETs. Finally, avoid PWM frequencies below 100 Hz for visible-light LEDs to prevent perceived flicker.
Compliance-Informationen
RoHS compliant per NXP product page. Lead-free TSSOP-28 package. Not AEC-Q100 qualified; use PCA9685PW/Q900,118 for automotive.
