PCA9532: 16-bit I2C-bus LED dimmer

The PCA9532 is a 16-bit I²C-bus and SMBus I/O expander optimized for dimming LEDs in 256 discrete steps for Red/Green/Blue (RGB) color mixing and back light applications.

The PCA9532 contains an internal oscillator with two user programmable blink rates and duty cycles coupled to the output PWM. The LED brightness is controlled by setting the blink rate high enough (> 100 Hz) that the blinking cannot be seen and then using the duty cycle to vary the amount of time the LED is on and thus the average current through the LED.

The initial setup sequence programs the two blink rates/duty cycles for each individual PWM. From then on, only one command from the bus master is required to turn individual LEDs ON, OFF, BLINK RATE 1 or BLINK RATE 2. Based on the programmed frequency and duty cycle, BLINK RATE 1 and BLINK RATE 2 will cause the LEDs to appear at a different brightness or blink at periods up to 1.69 second. The open-drain outputs directly drive the LEDs with maximum output sink current of 25 mA per bit and 200 mA per package (100 mA per octal).

To blink LEDs at periods greater than 1.69 second the bus master (MCU, MPU, DSP, chip set, etc.) must send repeated commands to turn the LED on and off as is currently done when using normal I/O expanders like the NXP Semiconductors PCF8575 or PCA9555. Any bits not used for controlling the LEDs can be used for General Purpose parallel Input/Output (GPIO) expansion, which provides a simple solution when additional I/O is needed for ACPI power switches, sensors, push-buttons, alarm monitoring, fans, etc.

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).

Three hardware address pins on the PCA9532 allow eight devices to operate on the same bus.

Outline 3d SOT137-1
Data Sheets (1)
Name/DescriptionModified Date
16-bit I2C-bus LED dimmer (REV 4.1) PDF (311.0 kB) PCA953222 Aug 2016
Application Notes (3)
Name/DescriptionModified Date
Level shifting techniques in I2C-bus design (REV 1.0) PDF (52.0 kB) AN1044120 Jun 2007
I2C manual (REV 1.0) PDF (4.2 MB) AN1021627 Mar 2003
I2C Devices for LED Display Control (REV 1.0) PDF (1.0 MB) AN26422 Jul 2002
Users Guides (5)
Name/DescriptionModified Date
PCA9532 demonstration board OM13528 (REV 1.0) PDF (405.0 kB) UM1098804 May 2016
I2C-bus specification and user manual (REV 6.0) PDF (1.4 MB) UM1020428 Apr 2014
I2C-bus specification and user manual (REV 5.0) PDF (1.6 MB) UM10204_JA03 Apr 2013
PCA9633 demonstration board OM6282 (REV 1.0) PDF (337.0 kB) UM1031715 Dec 2008
I2C Demonstration Board 2005-1 Quick Start Guide (REV 1.0) PDF (261.0 kB) UM1020613 Jun 2006
Brochures (4)
Name/DescriptionModified Date
NXP® I2C-bus solutions 2014: Smart, simple solutions for the 12 most common design concerns (REV 1.0) PDF (3.5 MB) 7501754001 Aug 2014
LED controllers: Voltage-switch drivers, constant-current drivers, and Flash LED drivers (REV 1.0) PDF (2.7 MB) 7501758803 Jul 2014
Create smarter, more efficient white goods; An industry-leading portfolio of cost-effective, power-saving solutions for... (REV 1.0) PDF (1.1 MB) 7501654301 Jun 2008
LED dimming with GPIO expansion; NXP® 2/4/8/16-bit I2C/SMBus LED dimmers PCA9530/31/32/33 (REV 1.0) PDF (212.0 kB) 7501607301 Jun 2007
Package Information (3)
Name/DescriptionModified Date
plastic small outline package; 24 leads; body width 7.5 mm (REV 1.0) PDF (379.0 kB) SOT137-108 Feb 2016
plastic thin shrink small outline package; 24 leads; body width 4.4 mm (REV 1.0) PDF (353.0 kB) SOT355-108 Feb 2016
plastic thermal enhanced very thin quad flat package; no leads; 24 terminals; body 4 x 4 x 0.85 mm (REV 1.0) PDF (202.0 kB) SOT616-108 Feb 2016
Packing (3)
Name/DescriptionModified Date
HVQFN24; reel pack; standard product orientation; 12NC ending 118 (REV 1.0) PDF (196.0 kB) SOT616-1_11816 Jan 2014
TSSOP24; Reel pack; SMD, 13" Q1/T1 Standard product orientation Orderable part number ending ,118 or... (REV 4.1) PDF (227.0 kB) SOT355-1_11815 Apr 2013
SO24; Reel pack; SMD, 13" Q1/T1 Standard product orientation Orderable part number ending ,118 or J Ordering... (REV 4.0) PDF (235.0 kB) SOT137-1_11812 Apr 2013
Reports or Presentations (1)
Name/DescriptionModified Date
design_con_2003_tecforum_i2c_b_1 (REV 0.1) PDF (4.2 MB) DESIGN_CON_2003_TECFORUM_I2C_B_127 Jan 2003
Supporting Information (2)
Name/DescriptionModified Date
Footprint for wave soldering (REV 1.0) PDF (8.0 kB) SO-SOJ-WAVE08 Oct 2009
Footprint for wave soldering (REV 1.0) PDF (16.0 kB) SSOP-TSSOP-VSO-WAVE08 Oct 2009
IBIS Model
Ordering Information
ProductStatusPackage versionOperating Temperature (Cel)PWMsReset input pinI2C-bus (kHz)Operating voltage (VDC)Max Sink Current per bit (mA)No of AddressesMax Sink Current, per package (mA)Number of bits
PCA9532DActiveSOT137-1-40~852 (160 Hz to 1.6 sec)yes4002.3~5.525820016
PCA9532PWActiveSOT355-1-40~852 (160 Hz to 1.6 sec)yes4002.3~5.525820016
PCA9532BSActiveSOT616-1-40~852 (160 Hz to 1.6 sec)yes4002.3~5.525820016
Package Information
Product IDPackage DescriptionOutline VersionReflow/Wave SolderingPackingProduct StatusPart NumberOrdering code(12NC)MarkingChemical ContentRoHS / Pb Free / RHFLeadFree Conversion DateEFRIFR(FIT)MTBF(hour)MSLMSL LF
PCA9532BSSOT616-1Reel 13" Q1/T1ActivePCA9532BS,118 (9352 728 39118)9532PCA9532BSAlways Pb-free0.02.05E811
PCA9532DSOT137-1SO-SOJ-WAVEReel 13" Q1/T1ActivePCA9532D,118 (9352 728 38118)PCA9532DPCA9532Dweek 5, 20050.02.05E811
Bulk PackActivePCA9532D,112 (9352 728 38112)PCA9532DPCA9532Dweek 5, 20050.02.05E811
PCA9532PWSOT355-1SSOP-TSSOP-VSO-WAVEReel 13" Q1/T1ActivePCA9532PW,118 (9352 728 37118)PCA9532PWPCA9532PWweek 12, 20050.02.05E811
Bulk PackActivePCA9532PW,112 (9352 728 37112)PCA9532PWPCA9532PWweek 12, 20050.02.05E811
PCA9532PW/S908SOT355-1SSOP-TSSOP-VSO-WAVEReel 13" Q1/T1ActivePCA9532PW/S908,118 (9352 895 87118)PCA9532PWPCA9532PW/S908Always Pb-free0.02.05E811
16-bit I2C-bus LED dimmer PCA9532
Level shifting techniques in I2C-bus design pca9685pw
I2C manual se98apw
I2C Devices for LED Display Control PCA9553
PCA9532 demonstration board OM13528 PCA9532
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
Create smarter, more efficient white goods; An industry-leading portfolio of cost-effective, power-saving solutions for... PMEG6010CE_AUTOMOTIVE
LED dimming with GPIO expansion; NXP® 2/4/8/16-bit I2C/SMBus LED dimmers PCA9530/31/32/33 PCA9551
design_con_2003_tecforum_i2c_b_1 lm75a
PCA9532 IBIS model PCA9532PW
plastic thermal enhanced very thin quad flat package; no leads; 24 terminals; body 4 x 4 x 0.85 mm TFF1007HN
HVQFN24; reel pack; standard product orientation; 12NC ending 118 TFF1007HN
plastic small outline package; 24 leads; body width 7.5 mm 74LVC4245A_Q100
Footprint for wave soldering NPIC6C596A_Q100
SO24; Reel pack; SMD, 13" Q1/T1 Standard product orientation Orderable part number ending ,118 or J Ordering... 74LVC4245A_Q100
plastic thin shrink small outline package; 24 leads; body width 4.4 mm 74LVC4245A_Q100
SSOP-TSSOP-VSO-WAVE LPC1114FDH28
TSSOP24; Reel pack; SMD, 13" Q1/T1 Standard product orientation Orderable part number ending ,118 or... 74LVC4245A_Q100
TFF11152HN
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