PCA9553 2 4-bit I C-bus LED driver with programmable blink rates Rev. 06 29 December 2008 Product data sheet 1. General description 2 The PCA9553 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 PCA9553 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 100 mA per package. Any bits not used for controlling the LEDs can be used for General Purpose Parallel Input/Output (GPIO) expansion. Power-On Reset (POR) initializes the registers to their default state, all zeroes, causing the bits to be set HIGH (LED off). Due to pin limitations, the PCA9553 is not featured with hardware address pins. The 2 PCA9553/01 and the PCA9553/02 have different xed I C-bus addresses allowing operation of both on the same bus. 2. Features n 4 LED drivers (on, off, ashing at a programmable rate) n 2 selectable, fully programmable blink rates (frequency and duty cycle) between 0.172 Hz and 44 Hz (5.82 seconds and 0.023 seconds) n Input/outputs not used as LED drivers can be used as regular GPIOs n Internal oscillator requires no external components 2 n I C-bus interface logic compatible with SMBus n Internal power-on reset n Noise lter on SCL/SDA inputs n 4 open-drain outputs directly drive LEDs to 25 mA n Controlled edge rates to minimize ground bounce n No glitch on power-up n Supports hot insertion n Low standby current n Operating power supply voltage range of 2.3 V to 5.5 V n 0 Hz to 400 kHz clock frequencyPCA9553 NXP Semiconductors 2 4-bit I C-bus LED driver with programmable blink rates n ESD protection exceeds 2000 V HBM per JESD22-A114, 150 V MM per JESD22-A115 and 1000 V CDM per JESD22-C101 n Latch-up testing is done to JEDEC Standard JESD78 which exceeds 100 mA n Packages offered: SO8, TSSOP8 (MSOP8), HVSON8 3. Ordering information Table 1. Ordering information Type number Package Name Description Version PCA9553D/01 SO8 plastic small outline package 8 leads SOT96-1 body width 3.9 mm PCA9553D/02 1 PCA9553DP/01 TSSOP8 plastic thin shrink small outline package 8 leads SOT505-1 body width 3 mm PCA9553DP/02 2 PCA9553TK HVSON8 plastic thermal enhanced very thin small outline SOT908-1 package no leads 8 terminals body 3 3 0.85 mm PCA9553TK/02 1 Also known as MSOP8. 2 PCA9553TK uses version /01 address. 4. Marking Table 2. Marking codes Type number Marking code PCA9553D/01 9553/1 PCA9553D/02 9553/2 PCA9553DP/01 P53/1 PCA9553DP/02 P53/2 PCA9553TK P53/1 PCA9553TK/02 P53/2 PCA9553 6 NXP B.V. 2008. All rights reserved. Product data sheet Rev. 06 29 December 2008 2 of 26