PCA9550: 2-bit I2C-bus LED driver with programmable blink rates
The PCA9550 LED blinker blinks LEDs in I²C-bus and SMBus applications where it is necessary to limit bus traffic or free up the I²C master's (MCU, MPU, DSP, chip set, etc.) timer. The uniqueness of this device is the internal oscillator with two programmable blink rates. To blink LEDs using normal I/O expanders like the PCF8574 or PCA9554, the bus master must send repeated commands to turn the LED on and off. This greatly increases the amount of traffic on the I²C-bus and uses up one of the master's timers. The PCA9550 LED blinker instead requires only the initial set-up command to program BLINK RATE 1 and BLINK RATE 2 (i.e., the frequency and duty cycle). From then on, only one command from the bus master is required to turn each individual open-drain output ON, OFF, or to cycle at BLINK RATE 1 or BLINK RATE 2. Maximum output sink current is 25 mA per bit and 50 mA per package.
Any bits not used for controlling the LEDs can be used for General Purpose parallel Input/Output (GPIO) expansion.
The active LOW hardware reset pin (RESET) and Power-On Reset (POR) initializes the registers to their default state, all zeroes, causing the bits to be set HIGH (LED off).
One hardware address pin on the PCA9550 allows two devices to operate on the same bus.
PCA9550: Product Block Diagram
sot096-1_3d
Data Sheets (1)
| Name/Description | Modified Date |
|---|---|
| 2-bit I2C-bus LED driver with programmable blink rates (REV 5.0) PDF (150.0 kB) PCA9550 | 13 Oct 2008 |
Application Notes (3)
| Name/Description | Modified Date |
|---|---|
| Level shifting techniques in I2C-bus design (REV 1.0) PDF (52.0 kB) AN10441 | 20 Jun 2007 |
| I2C 2002-1A Evaluation Board (REV 2.0) PDF (2.2 MB) AN10146 | 26 Feb 2003 |
| I2C Devices for LED Display Control (REV 1.0) PDF (1.0 MB) AN264 | 22 Jul 2002 |
Users Guides (4)
| Name/Description | Modified Date |
|---|---|
| I2C-bus specification and user manual (REV 6.0) PDF (1.4 MB) UM10204 | 28 Apr 2014 |
| I2C-bus specification and user manual (REV 5.0) PDF (1.6 MB) UM10204_JA | 03 Apr 2013 |
| PCA9633 demonstration board OM6282 (REV 1.0) PDF (337.0 kB) UM10317 | 15 Dec 2008 |
| I2C Demonstration Board 2005-1 Quick Start Guide (REV 1.0) PDF (261.0 kB) UM10206 | 13 Jun 2006 |
Brochures (5)
| Name/Description | Modified Date |
|---|---|
| NXP® I2C-bus solutions 2014: Smart, simple solutions for the 12 most common design concerns (REV 1.0) PDF (3.5 MB) 75017540 | 01 Aug 2014 |
| LED controllers: Voltage-switch drivers, constant-current drivers, and Flash LED drivers (REV 1.0) PDF (2.7 MB) 75017588 | 03 Jul 2014 |
| Evaluate the I2C-bus with a comprehensive kit; NXP® I2C 2002-1A evaluation board kits OM6285 and OM6278 (REV 1.0) PDF (1.8 MB) 75016531 | 01 Jul 2008 |
| Create smarter, more efficient white goods; An industry-leading portfolio of cost-effective, power-saving solutions for... (REV 1.0) PDF (1.1 MB) 75016543 | 01 Jun 2008 |
| LED blinking with GPIO expansion; NXP® 2/4/8/16-bit I2C/SMBus LED blinkers PCA9550/51/52/53 (REV 1.0) PDF (219.0 kB) 75016021 | 01 Jun 2007 |
Package Information (2)
| Name/Description | Modified Date |
|---|---|
| plastic thin shrink small outline package; 8 leads; body width 3 mm (REV 1.0) PDF (240.0 kB) SOT505-1 | 08 Feb 2016 |
| plastic small outline package; 8 leads; body width 3.9 mm (REV 1.0) PDF (244.0 kB) SOT96-1 | 08 Feb 2016 |
Packing (2)
| Name/Description | Modified Date |
|---|---|
| SO8; Reel pack; SMD, 13" Q1/T1 Standard product orientation Orderable part number ending ,118 or J Ordering... (REV 2.0) PDF (232.0 kB) SOT96-1_118 | 19 Apr 2013 |
| TSSOP8; Reel pack; SMD, 13" Q1/T1 Standard product orientation Orderable part number ending ,118 or... (REV 1.0) PDF (214.0 kB) SOT505-1_118 | 15 Apr 2013 |
Reports or Presentations (1)
| Name/Description | Modified Date |
|---|---|
| design_con_2003_tecforum_i2c_b_1 (REV 0.1) PDF (4.2 MB) DESIGN_CON_2003_TECFORUM_I2C_B_1 | 27 Jan 2003 |
Supporting Information (4)
| Name/Description | Modified Date |
|---|---|
| Reflow Soldering Profile (REV 1.0) PDF (34.0 kB) REFLOW_SOLDERING_PROFILE | 30 Sep 2013 |
| Wave Soldering Profile (REV 1.0) PDF (20.0 kB) WAVE_SOLDERING_PROFILE | 30 Sep 2013 |
| Footprint for reflow soldering (REV 1.0) PDF (9.0 kB) SO-SOJ-REFLOW | 08 Oct 2009 |
| Footprint for wave soldering (REV 1.0) PDF (8.0 kB) SO-SOJ-WAVE | 08 Oct 2009 |
IBIS Model
- PCA9550 IBIS model (REV 1.0) ibs PCA9550_1 9/2/2014
Ordering Information
| Product | Status | Package version | Operating Temperature (Cel) | PWMs | Reset input pin | I2C-bus (kHz) | Operating voltage (VDC) | Max Sink Current per bit (mA) | No of Addresses | Max Sink Current, per package (mA) | Number of bits |
|---|---|---|---|---|---|---|---|---|---|---|---|
| PCA9550D | Active | SOT96-1 | -40~85 | 2 (40 Hz to 6.4 sec) | yes | 400 | 2.3~5.5 | 25 | 2 | 50 | 2 |
| PCA9550DP | Active | SOT505-1 | -40~85 | 2 (40 Hz to 6.4 sec) | yes | 400 | 2.3~5.5 | 25 | 2 | 50 | 2 |
Package Information
| Product ID | Package Description | Outline Version | Reflow/Wave Soldering | Packing | Product Status | Part NumberOrdering code(12NC) | Marking | Chemical Content | RoHS / Pb Free / RHF | LeadFree Conversion Date | EFR | IFR(FIT) | MTBF(hour) | MSL | MSL LF |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PCA9550D | | SOT96-1 | SO-SOJ-REFLOW
SO-SOJ-WAVE SO-SOJ-REFLOW SO-SOJ-WAVE | Reel 13" Q1/T1 | Active | PCA9550D,118 (9352 728 82118) | PCA9550 | PCA9550D |    | week 5, 2005 | 0.0 | 2.0 | 5E8 | 1 | 1 |
| Bulk Pack | Active | PCA9550D,112 (9352 728 82112) | PCA9550 | PCA9550D | | week 5, 2005 | 0.0 | 2.0 | 5E8 | 1 | 1 | ||||
| PCA9550DP |  | SOT505-1 | Reflow_Soldering_Profile | Reel 13" Q1/T1 | Active | PCA9550DP,118 (9352 728 81118) | 9550 | PCA9550DP | | week 12, 2005 | 0.0 | 2.0 | 5E8 | 1 | 1 |
- Level shifting techniques in I2C-bus design pca9685pw
- I2C 2002-1A Evaluation Board lm75a
- I2C Devices for LED Display Control PCA9553
- I2C-bus specification and user manual pca9685pw
- I2C-bus specification and user manual pca9685pw
- PCA9633 demonstration board OM6282 pca9685pw
- I2C Demonstration Board 2005-1 Quick Start Guide pca9685pw
- NXP® I2C-bus solutions 2014: Smart, simple solutions for the 12 most common design concerns pca9685pw
- LED controllers: Voltage-switch drivers, constant-current drivers, and Flash LED drivers pca9685pw
- Evaluate the I2C-bus with a comprehensive kit; NXP® I2C 2002-1A evaluation board kits OM6285 and OM6278 lm75a
- Create smarter, more efficient white goods; An industry-leading portfolio of cost-effective, power-saving solutions for... PMEG6010CE_AUTOMOTIVE
- LED blinking with GPIO expansion; NXP® 2/4/8/16-bit I2C/SMBus LED blinkers PCA9550/51/52/53 PCA9553
- design_con_2003_tecforum_i2c_b_1 lm75a
- Reflow_Soldering_Profile Wave_Soldering_Profile LPC1112FD20
- PCA9550 IBIS model PCA9550DP
- plastic small outline package; 8 leads; body width 3.9 mm CBT3306_Q100
- Footprint for reflow soldering NPIC6C596A_Q100
- Footprint for wave soldering NPIC6C596A_Q100
- SO8; Reel pack; SMD, 13" Q1/T1 Standard product orientation Orderable part number ending ,118 or J Ordering... CBT3306_Q100
- plastic thin shrink small outline package; 8 leads; body width 3 mm pesd5v0l7bas
- Reflow_Soldering_Profile Wave_Soldering_Profile LPC1112FD20
- TSSOP8; Reel pack; SMD, 13" Q1/T1 Standard product orientation Orderable part number ending ,118 or... pesd5v0l7bas
- PCA9550
- SA612A
- PCT2075
