My Inquiry
My Account
NXP Semiconductors PCA9955ATWJ
- Part No.:
- PCA9955ATWJ
- Manufacturer:
- NXP Semiconductors
- Category:
- LED Drivers
- Package:
- 28-TSSOP (0.173", 4.40mm Width) Exposed Pad
- Datasheet:
-
PCA9955ATWJ.pdf
- Description:
- IC LED DRV LIN I2C 57MA 28HTSSOP
- Quantity:
- Payment:
- Shipping:
Inventory:3,195
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
PCA9955ATWJ from NXP Semiconductors is a 16-channel Fm+ I²C-bus constant current LED driver optimized for RGBA LED dimming and blinking in amusement products, with individual 8-bit PWM (31.25 kHz), group PWM (122 Hz to 16.8 s), 57 mA per channel, 20 V LED supply tolerance, and integrated open/short/overtemperature detection.
For engineers reviewing the PCA9955ATWJ datasheet, PCA9955ATWJ pinout, PCA9955ATWJ application, or PCA9955ATWJ equivalent, this device supports hardware blink control via OE, gradation ramping across four independent groups, Fast-mode Plus I²C up to 1 MHz, and scalable multi-device addressing with 125 unique slave addresses.
Technical Context
The PCA9955ATWJ integrates dual PWM architectures: per-channel 31.25 kHz PWM with 256-step linear brightness control and group-level PWM with programmable frequency (15 Hz–16.8 s) and 256-step duty cycle (0–99.6%). It uses an internal 8 MHz oscillator and supports gradation control with independently configurable ramp-up/ramp-down rates, step time (0.5–512 ms), hold times (0–6 s), and final output current per group.
Its I²C interface implements Fast-mode Plus (1 MHz), 30 mA SDA drive strength, noise filtering on SCL/SDA, and three quinary address pins (AD0–AD2) enabling 125 unique slave addresses. The device features software reset (SWRST), LED Group/Sub Call addressing (E0h/ECh), and active-low OE for synchronized hardware dimming/blinking across multiple devices.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| LED Channels | 16 constant-current sink outputs, each programmable for off/on/PWM/group-PWM operation |
| Max Output Current | 57 mA per channel, adjustable via external REXT resistor and 8-bit DAC (225 µA–57 mA) |
| PWM Frequencies | Individual: fixed 31.25 kHz; Group: programmable 15 Hz to 16.8 s period (122 Hz default) |
| I²C Interface | Fast-mode Plus compatible, up to 1 MHz, 30 mA SDA drive, noise-filtered inputs |
| Gradation Control | 4 independent groups; each supports ramp-up/down rate, step time (6-bit), hold time (3-bit), and final current |
| Supply Range | VDD: 3.0 V to 5.5 V; LED supply up to 20 V (channel OFF state) |
| Operating Temp | −40 °C to +85 °C; ESD > 4000 V HBM; latch-up > 100 mA per JEDEC JESD78 |
Pinout & Package
PCA9955ATWJ is packaged in HTSSOP28 (SOT1172-3): thermally enhanced 28-pin thin shrink small outline package with 0.65 mm pitch, 4.4 mm body width, and exposed die pad connected to VSS.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| REXT (1) | Current set reference input | Connects external resistor to ground to calibrate all 16 output currents linearly |
| AD0–AD2 (2–4) | Quinary address inputs | Determine one of 125 possible I²C slave addresses at power-up; require stable bias before VDD |
| OE (5) | Active-low output enable | Hardware blink/dim control; overrides all LED states when asserted |
| LED0–LED15 (6–9, 11–18, 20–23) | Constant-current LED sinks | 16 individually controllable outputs; each tolerates up to 20 V when OFF |
| RESET (25) | Active-low hardware reset | Resets registers to POR defaults; output current switches go OFF |
| SCL/SDA (26/27) | I²C bus interface | Fm+ compliant; SDA supports 30 mA drive for high-capacitance buses |
| VDD (28) | Power supply | 3.0 V–5.5 V digital/analog core supply |
| VSS (10, 19, 24, thermal pad) | Ground reference | All VSS pins and exposed pad must be connected to system ground; thermal pad requires soldering and vias for thermal management |
Key Features
| Feature | Design Value |
|---|---|
| Independent + group PWM control | Enables simultaneous fine-grained per-LED brightness and synchronized global blink/dim without MCU intervention |
| Four gradation control groups | Each group supports programmable ramp timing, hold duration, and final current-ideal for breath-lighting and smooth transitions |
| Open/short/overtemperature detection | Per-channel fault reporting via I²C-readable registers enables real-time LED health monitoring and system diagnostics |
| 125-device I²C scalability | Three quinary address pins eliminate address conflicts in large LED arrays (e.g., signage, stage lighting) |
| Software Reset (SWRST) | Allows full register reinitialization over I²C-identical to POR-enabling rapid recovery or configuration reload |
| LED Group/Sub Call addressing | E0h All Call and three ECh Sub Call addresses allow coordinated control of LED subsets (e.g., all reds, marquee chase) |
Applications
| Amusement Lighting Control | RGB/RGBA Status Indication |
|---|---|
Use Scenario: Dynamic color sequencing and synchronized blinking in arcade cabinets, prize wheels, and interactive kiosks. IC Role / Device Role / Timing Role: 16-channel constant-current sink with dual PWM layers and hardware OE for frame-accurate visual effects. Use Value: Eliminates MCU PWM overhead; enables complex fade-in/fade-out, breathing, and strobe patterns using only I²C commands. |
Use Scenario: Multi-color status feedback on industrial HMIs, medical devices, and test equipment panels. IC Role / Device Role / Timing Role: Independent brightness control per LED channel plus group-level dimming for unified intensity scaling. Use Value: Ensures consistent color perception across varying ambient light via precise 256-step linear current control per channel. |
| LED Display Backlighting | Automotive Interior Lighting |
Use Scenario: Edge-lit or direct-lit backlight for small-format LCDs in handheld devices and instrumentation displays. IC Role / Device Role / Timing Role: Constant-current driver with 20 V LED supply tolerance supporting series-connected LED strings. Use Value: Maintains uniform luminance across display area while minimizing EMI through programmable LED output delay. |
Use Scenario: Ambient lighting, door courtesy lights, and dashboard accent illumination in automotive cabins. IC Role / Device Role / Timing Role: AEC-Q100 qualified variant (PCA9955ATW/Q900) supports automotive temperature and reliability requirements. Use Value: Integrated thermal shutdown and fault detection ensure safe operation under extended cabin temperature excursions. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar LED driver applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TLC5940 (Texas Instruments) | 16-channel, 12-bit PWM resolution, no group PWM, no gradation control, 17 V max LED voltage | Lacks synchronized blink, ramping, and fault detection; suited for static brightness control only | Select when higher grayscale depth is required and group-level animation is unnecessary |
| IS31FL3731 (Lumissil) | 18-channel, 8-bit PWM, built-in breathing engine, 28 V LED voltage, I²C up to 400 kHz | Includes dedicated breathing hardware but lacks quinary addressing and Fm+ speed; no open-load detection | Prefer for compact breathing-only designs where I²C bandwidth < 1 MHz is acceptable |
Compared with TLC5940 and IS31FL3731, PCA9955ATWJ uniquely combines Fm+ I²C scalability, hardware blink synchronization via OE, four independent gradation groups, and comprehensive fault reporting-making it optimal for complex, maintenance-aware amusement and industrial lighting systems.
Availability
PCA9955ATWJ is available at Aetrix Electronics and suitable for amusement lighting control, RGB/RGBA status indication, and LED display backlighting requiring stable component supply, long-term production continuity, and automotive-grade variants.
Supply support for PCA9955ATWJ 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 specializing in secure connectivity solutions for automotive, industrial, and IoT applications, with deep expertise in mixed-signal and interface ICs.
The PCA9955A product line was designed specifically for high-reliability, multi-LED visual systems in amusement, signage, and automotive interior lighting-emphasizing scalable control, fault resilience, and low-MCU-footprint animation.
FAQ
What is the maximum LED supply voltage supported by PCA9955ATWJ?
The PCA9955ATWJ LED outputs tolerate up to 20 V when in the OFF state, enabling use with medium-length LED strings powered from common 12 V or 19 V rails. This rating is independent of the 3.0–5.5 V VDD supply and applies to all 16 sink channels. The actual forward voltage of connected LEDs must remain within the 20 V limit at all times.
How does the PCA9955ATWJ implement gradation control for LED fading effects?
The PCA9955ATWJ provides four independent gradation groups, each configurable with ramp-up/ramp-down rate, step time (0.5–512 ms), hold-on/off time (0–6 s), and final output current. Each LED channel can be assigned to any group and operate in either gradation or normal mode-enabling synchronized breathing, cross-fading, or staggered transitions without MCU involvement.
Can PCA9955ATWJ be used in automotive applications?
Yes-the PCA9955ATWJ's automotive-qualified variant PCA9955ATW/Q900 is AEC-Q100 qualified and operates from −40 °C to +85 °C. While PCA9955ATWJ itself is rated for the same temperature range and includes thermal shutdown and fault detection, only the /Q900 suffix guarantees full automotive qualification and PPAP documentation support.
What is the purpose of the OE (Output Enable) pin on PCA9955ATWJ?
The active-low OE pin on PCA9955ATWJ forces all 16 LED outputs into blink mode regardless of internal PWM settings. When pulsed externally, it enables hardware-synchronized dimming or blinking across multiple PCA9955ATWJ devices-eliminating I²C bus traffic and timing jitter associated with software-controlled updates.
How many unique I²C addresses can be configured on a single bus using PCA9955ATWJ?
PCA9955ATWJ supports up to 125 unique I²C slave addresses via three quinary address pins (AD0–AD2), each configurable in five states (GND, VDD, floating, pull-up, pull-down). This allows dense deployment on a single bus-for example, 125 devices × 16 channels = 2000 individually addressable LEDs with minimal address management overhead.
PCA9955ATWJ Specifications
- Product attributes
- Attribute value
- Manufacturer:
- NXP Semiconductors
- Series:
- -
- Package/Case:
- 28-TSSOP (0.173", 4.40mm Width) Exposed Pad
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- Linear
- Topology:
- -
- Internal Switch(s):
- Yes
- Number of Outputs:
- 16
- Voltage - Supply (Min):
- 3V
- Voltage - Supply (Max):
- 5.5V
- Voltage - Output:
- 20V
- Current - Output / Channel:
- 57mA
- Frequency:
- 8MHz
- Dimming:
- I2C
- Applications:
- Backlight
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 28-HTSSOP
PCA9955ATWJ FAQ
1.How can I place an order for PCA9955ATWJ through Aetrix?
Please submit a Request for Quotation (RFQ) for PCA9955ATWJ on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for PCA9955ATWJ reliable?
The price and inventory of PCA9955ATWJ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for PCA9955ATWJ is usually 5 days.
3.What payment methods are accepted for PCA9955ATWJ?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for PCA9955ATWJ transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for PCA9955ATWJ?
PCA9955ATWJ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your PCA9955ATWJ order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for PCA9955ATWJ?
For technical support, including PCA9955ATWJ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your PCA9955ATWJ requirements.
6.How does Aetrix verify that PCA9955ATWJ is sourced from the original manufacturer or authorized distributors?
All PCA9955ATWJ products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that PCA9955ATWJ meets industry standards.
7.What is the process for return or replacement of PCA9955ATWJ?
All PCA9955ATWJ units undergo pre-shipment inspection (PSI). If there is an issue with PCA9955ATWJ, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The PCA9955ATWJ part is unused and in its original packaging.
Return procedure for PCA9955ATWJ:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
PCA9955ATWJ Tags
-
BCR402RE6327HTSA1
Infineon Technologies
-
BCR430UXTSA2
Infineon Technologies
-
BCR420UE6433HTMA1
Infineon Technologies
-
BCR420UE6327HTSA1
Infineon Technologies
-
BCR421UE6327HTSA1
Infineon Technologies
-
LYT1604D-TL
Power Integrations
-
HV9910CLG-G
Microchip Technology
-
CL2N8-G
Microchip Technology
-
BCR420UW6-7
Diodes Incorporated
-
BCR421UW6-7
Diodes Incorporated
-
BCR420UFD-7
Diodes Incorporated
-
BCR421UFD-7
Diodes Incorporated
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
