PCA9552 2 16-bit I C-bus LED driver with programmable blink rates Rev. 05 9 March 2006 Product data sheet 1. General description 2 The PCA9552 LED blinker blinks LEDs in I C-bus and SMBus applications where it is 2 necessary to limit bus trafc or free up the I C-bus 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 2 increases the amount of trafc on the I C-bus and uses up one of the master s timers. The PCA9552 LED blinker instead requires only the initial setup command to program BLINK RATE 1 and BLINK RATE 2 (that is, the frequency and duty cycle) for each individual output. 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 200 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). Three hardware address pins on the PCA9552 allow eight devices to operate on the same bus. 2. Features 16 LED drivers (on, off, ashing at a programmable rate) 2 selectable, fully programmable blink rates (frequency and duty cycle) between 0.172 Hz and 44 Hz (5.82 seconds and 0.023 seconds) Input/outputs not used as LED drivers can be used as regular GPIOs Internal oscillator requires no external components 2 I C-bus interface logic compatible with SMBus Internal power-on reset Noise lter on SCL/SDA inputs Active LOW reset input 16 open-drain outputs directly drive LEDs to 25 mA Edge rate control on outputs No glitch on power-up Supports hot insertion Low standby current Operating power supply voltage range of 2.3 V to 5.5 V 0 Hz to 400 kHz clock frequencyPCA9552 Philips Semiconductors 2 16-bit I C-bus LED driver with programmable blink rates ESD protection exceeds 2000 V HBM per JESD22-A114, 150 V MM per JESD22-A115 and 1000 V CDM per JESD22-C101 Latch-up testing is done to JEDEC Standard JESD78 which exceeds 100 mA Packages offered: SO24, TSSOP24, HVQFN24 3. Ordering information Table 1: Ordering information T = - 40 C to +85 C amb Type number Topside mark Package Name Description Version PCA9552D PCA9552D SO24 plastic small outline package 24 leads body width 7.5 mm SOT137-1 PCA9552PW PCA9552 TSSOP24 plastic thin shrink small outline package 24 leads SOT355-1 body width 4.4 mm PCA9552BS 9552 HVQFN24 plastic thermal enhanced very thin quad at package SOT616-1 no leads 24 terminals body 4 4 0.85 mm 4. Block diagram A0 A1 A2 PCA9552 INPUT REGISTER SCL 2 INPUT I C-BUS LED SELECT (LSn) FILTERS CONTROL REGISTER SDA 1 0 V DD POWER-ON LEDn RESET RESET BLINK0 PRESCALER 0 PWM0 REGISTER REGISTER BLINK1 PRESCALER 1 PWM1 OSCILLATOR REGISTER REGISTER V SS 002aac168 Remark: Only one I/O shown for clarity. Fig 1. Block diagram of PCA9552 PCA9552 5 Koninklijke Philips Electronics N.V. 2006. All rights reserved. Product data sheet Rev. 05 9 March 2006 2 of 28