PCA9551D datasheet(11/21 Pages) PHILIPS

Part #	PCA9551D

Description	8-bit I2C LED driver with programmable blink rates

PDF	21 Pages

Scroll/Zoom	100%

Manufacturer	PHILIPS [NXP Semiconductors]

Direct Link	http://www.nxp.com

Logo

11 / 21 page

Philips Semiconductors

Product data sheet

PCA9551

8-bit I2C LED driver with programmable blink rates

2004 Oct 01

Programming example

The following example will show how to set LED0 to LED3 on. It will

then set LED4 and LED5 to blink at 1 Hz at a 50% duty cycle. LED6

and LED7 will be set to blink at 4 Hz and at a 25% duty cycle.

Table 1.

I2C-bus

Start

PCA9551 address with A0–A2 = LOW

C0h

PSC0 subaddress + auto-increment

11h

Set prescaler PSC0 to achieve a period of 1 second:

Blink period

+ 1 + PSC0 ) 1

PSC0 = 37

25h

Set PWM0 duty cycle to 50%:

256 – PWM0

256

+ 0.5

PWM0 = 128

80h

Set prescaler PCS1 to achieve a period of 0.25

seconds:

Blink period

+ 0.25 + PSC1 ) 1

PSC1 = 9

09h

Set PWM1 output duty cycle to 25%:

256 – PWM1

256

+ 0.25

PWM1 = 192

C0h

Set LED0 to LED3 on

00h

Set LED4 and 5 to PWM0, and LED6 or 7 to PWM1

FAh

Stop

PCA9551D Datasheet(PDF) 11 Page - NXP Semiconductors

PCA9551D Datasheet(HTML) 11 Page - NXP Semiconductors

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

Datasheet Download

Link URL