PCA9550D NXP Semiconductors, PCA9550D Datasheet - Page 6

• Manufacturer Part Number: PCA9550D
• Description: LED Drivers 2-BIT I2C FM OD LED BLK RST
• Manufacturer: NXP Semiconductors

Specifications of PCA9550D

• Number Of Segments: 2
• Low Level Output Current: 24000 uA (Min)
• Operating Supply Voltage: 2.3 V to 5.5 V
• Maximum Supply Current: 500 uA
• Maximum Power Dissipation: 400 mW
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: SOT-96
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: PCA9550D,112

NXP Semiconductors
PCA9550_5
Product data sheet
6.3.4 PSC1 - Frequency Prescaler 1
6.3.5 PWM1 - Pulse Width Modulation 1
6.3.6 LS0 - LED selector
PSC1 is used to program the period of the PWM output.
The period of BLINK1 = (PSC1 + 1) / 44.
Table 8.
The PWM1 register determines the duty cycle of BLINK1. The outputs are LOW (LED off)
when the count is less than the value in PWM1 and HIGH when it is greater. If PWM1 is
programmed with 00h, then the PWM1 output is always LOW.
The duty cycle of BLINK1 = (256
Table 9.
The LS0 LED select register determines the source of the LED data.
Table 10.
Bit
Symbol
Default
Bit
Symbol
Default
Bit
Symbol
Default
00 = output is set LOW (LED on)
01 = output is set high-impedance (LED off; default)
10 = output blinks at PWM0 rate
11 = output blinks at PWM1 rate
PSC1 - Frequency Prescaler 1 register description
PSC1[7]
PWM1 - Pulse Width Modulation 1 register description
LS0 - LED selector register description
PWM1
[7]
7
1
7
1
7
1
PSC1[6]
PWM1
Rev. 05 — 13 October 2008
[6]
6
1
6
0
6
1
LS0[7:4]
2-bit I
PSC1[5]
PWM1
[5]
5
1
5
0
5
1
PWM1) / 256.
2
C-bus LED driver with programmable blink rates
PSC1[4]
PWM1
[4]
4
1
4
0
4
1
PSC1[3]
PWM1
[3]
3
1
3
0
3
0
LED1
PSC1[2]
PWM1
[2]
2
2
0
2
1
1
PCA9550
PSC1[1]
© NXP B.V. 2008. All rights reserved.
PWM1
[1]
1
1
1
0
1
0
LED0
PSC1[0]
PWM1
[0]
0
1
0
0
0
1
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