PCA9532 Philips Semiconductors (Acquired by NXP), PCA9532 Datasheet - Page 5

• Manufacturer Part Number: PCA9532
• Description: PCA9532; 16-bit I2C Led Dimmer
• Manufacturer: Philips Semiconductors (Acquired by NXP)

Philips Semiconductors
DEVICE ADDRESSING
Following a START condition the bus master must output the
address of the slave it is accessing. The address of the PCA9532 is
shown in Figure 4. To conserve power, no internal pull-up resistors
are incorporated on the hardware selectable address pins and they
must be pulled HIGH or LOW.
The last bit of the address byte defines the operation to be
performed. When set to logic 1 a read is selected while a logic 0
selects a write operation.
CONTROL REGISTER
Following the successful acknowledgement of the slave address,
the bus master will send a byte to the PCA9532 which will be stored
in the Control Register. This register can be read and written via the
I
CONTROL REGISTER DEFINITION
REGISTER DESCRIPTION
The lowest 3 bits are used as a pointer to determine which register
will be accessed.
2003 May 02
2
C-bus.
B3
0
0
0
0
0
0
0
0
1
1
16-bit I
RESET STATE: 00h
B2
0
0
0
0
1
1
1
1
0
0
B1
2
0
0
1
1
0
0
1
1
0
0
C LED dimmer
0
1
Figure 5. Control register
B0
Figure 4. Slave address
0
1
0
1
0
1
0
1
0
1
0
1
FIXED
0
REGISTER
SLAVE ADDRESS
0
INPUT0
INPUT1
AUTO-INCREMENT FLAG
PWM0
PWM1
NAME
PSC0
PSC1
LS0
LS1
LS2
LS3
AI
0
REGISTER ADDRESS
B3
A2
HARDWARE SELECTABLE
B2
A1 A0
WRITE
WRITE
WRITE
WRITE
WRITE
WRITE
WRITE
WRITE
READ/
READ/
READ/
READ/
READ/
READ/
READ/
READ/
READ
READ
TYPE
B1
R/W
B0
PRESCALER 0
PRESCALER 1
FREQUENCY
FREQUENCY
REGISTER 0
REGISTER 1
REGISTER 0
REGISTER 1
SELECTOR
SELECTOR
SELECTOR
SELECTOR
FUNCTION
REGISTER
LED 12-15
LED 8-11
LED 0-3
LED 4-7
INPUT
INPUT
SW00898
PWM
PWM
su01420
5
If the auto-increment flag (AI) is set, the four low order bits of the
Control Register are automatically incremented after a read or write.
This allows the user to program the registers sequentially. The
contents of these bits will rollover to ‘0000’ after the last register is
accessed.
When auto-increment flag is set (AI = 1) and a read sequence is
initiated, the sequence must start by reading a register different from
‘0’ (B3 B2 B1 B0 0 0 0 0 0)
Only the 4 least significant bits are affected by the AI flag.
Unused bits must be programmed with zeroes.
INPUT0 — INPUT REGISTER 1
The INPUT register 1 reflects the state of the device pins (inputs 0
to 7). Writes to this register will be acknowledged but will have no
effect.
INPUT1 — INPUT REGISTER 2
The INPUT register 1 reflects the state of the device pins (inputs 8
to 15). Writes to this register will be acknowledged but will have no
effect.
PSC0 — FREQUENCY PRESCALER 0
PSC0 is used to program the period of the PWM output.
The period of BLINK0 +
PWM0 — PWM REGISTER 0
The PWM0 register determines the duty cycle of BLINK0. The
outputs are LOW (LED on) when the count is less than the value in
PWM0 and HIGH (LED off) when it is greater. If PWM0 is
programmed with 00h, then the PWM0 output is always HIGH
(LED off).
The duty cycle of BLINK0 is: PWM0
PSC1 — FREQUENCY PRESCALER 1
PSC1 is used to program the period of PWM output.
The period of BLINK1 +
PWM1 — PWM REGISTER 1
The PWM1 register determines the duty cycle of BLINK1. The
outputs are LOW (LED on) when the count is less than the value in
PWM1 and HIGH (LED off) when it is greater. If PWM1 is
programmed with 00h, then the PWM1 output is always HIGH
(LED off).
The duty cycle of BLINK1 is: PWM1
default
default
default
default
default
default
bit
bit
bit
bit
bit
bit
I15
I7
0
0
7
0
7
1
7
0
7
1
I14
I6
0
0
6
0
6
0
6
0
6
0
(PSC0 ) 1)
(PSC1 ) 1)
I13
I5
0
0
5
0
5
0
5
0
5
0
152
152
256
256
I12
I4
0
0
4
0
4
0
4
0
4
0
I11
I3
0
0
3
0
3
0
3
0
3
0
I10
PCA9532
I2
0
0
2
0
2
0
2
0
2
0
Product data
I1
I9
0
0
1
0
1
0
1
0
1
0
I0
I8
0
0
0
0
0
0
0
0
0
0