4-Bit I²C-Bus LED Driver

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This driver, optimized for RGBA color mixing, can set each of the four LEDs to a specific brightness value and can dim or blink all of them with the same value. Available in a variety of pin-out and package combinations, it also offers special software features that optimize I2C-bus commands in multi-LED control applications.

The PCA9633 is an I²C-bus controlled 4-bit LED driver optimized for red, green, blue and amber (RGBA) color mixing applications. Each LED output has its own 8-bit resolution (256 steps) fixed frequency, individual PWM controller that operates at 97kHz with a duty cycle that is adjustable from 0 percent to 99.6 percent to allow the LED to be set to a specific brightness value. A fifth 8-bit resolution (256 steps) group PWM controller has both a fixed frequency of 190Hz and an adjustable frequency between 24Hz to once every 10.73 seconds with a duty cycle that is adjustable from 0 percent to 99.6 percent that is used to either dim or blink all LEDs with the same value.

Each LED output can be off, on (no PWM control), set at its individual PWM controller value or at both individual and group PWM controller values. The LED output driver is programmed to be either open drain (25mA sink capability at 5V) or totem pole (25mA sink/10mA source capability at 5V).

Software programmable LED group and three sub call I²C addresses allow all or defined groups to respond to a common I²C address allowing all LEDs of a certain color to be turned on/off at the same time or marquee chasing effect, minimizing I²C bus commands.

 

FEATURES 4 LED drivers, 25mA output drive Each LED driver programmable to Off On Programmable brightness Programmable group dimming/blinking mixed with individual LED brightness 2.3V to 5.5V power supply input range 25MHz fully internal oscillator Operating temperature range: -40°C to +85°C 1MHz fast mode plus compatible I2C protocol with 30MHz high drive capability on SDA output 3 versions: One device per bus (one fixed I2C bus address) Four devices per bus (two I2C bus address lines) 128 devices per bus (seven I2C bus address lines) Software reset feature allows device to be reset via I2C bus Internal power-on reset Edge rate control on outputs 5V tolerant inputs RoHS-compliant 256-step (8-bit) linear programmable brightness per LED output varying from fully off (default) to maximum brightness using a 97kHz PWM signal 256-step group brightness control allows general dimming (using a 190Hz PWM signal) from fully off to maximum brightness (default) 256-step group blinking with frequency programmable from 24Hz to 10.73 s and duty cycle from 0 pct to 99.6 pct Four totem-pole outputs (sink 25mA and source 10mA at 5V) with software programmable open-drain LED outputs selection (default at totem-pole). No input function. Output state change programmable on the Acknowledge or the STOP Command to update outputs byte-by-byte or all at the same time (default to 'Change on STOP'). Active LOW Output Enable (OE) input pin. LED outputs programmable to '1', '0' or 'high-impedance' (default at power-up) when OE is HIGH, thus allowing hardware blinking and dimming of the LEDs (16-pin version only). 2 hardware address pins (10-pin version) and 7 hardware address pins (16-pin version) allow respectively up to 4 and 126 PCA9633 devices to be connected to the same I2C-bus. No hardware address pins in the 8-pin version. 4 software programmable I2C-bus addresses (one LED Group Call address and three LED Sub Call addresses) allow groups of devices to be addressed at the same time in any combination (for example, one register used for 'All Call' so that all the PCA9633s on the I2C-bus can be addressed at the same time and the second register used for three different addresses so that 1/3 of all devices on the bus can be addressed at the same time in a group). Software enable and disable for I2C-bus address. Up to 126 possible hardware adjustable individual I2C-bus addresses per device so that each device can be programmed individually Noise filter on SDA/SCL inputs No glitch on power-up Supports hot insertion Low standby current ESD protection exceeds 2000 V HBM per JESD22-A114, 200 V MM per JESD22-A115, and 1000 V CDM per JESD22-C101 Latch-up testing is done to JEDEC Standard JESD78 which exceeds 100mA Packages offered: SO, TSSOP (MSOP), HVQFN, HVSON

APPLICATIONS RGB or RGBA LED drivers Decorative LED lighting LED status info LED displays and backlights Keypad backlights for cellular phones or handheld devices

 

 

 

Applications Notes

Level Shifting Techniques in I²C-bus Design

Driving LED Light Bars Using NXP Solutions

 

 

 Featured Products

Part Number		Description	Data Sheet	App. Notes
PCA9633DP2-T		4-bit Fm+ I2C-bus LED Driver

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