PCA9533D PHILIPS [NXP Semiconductors], PCA9533D Datasheet - Page 4

• Manufacturer Part Number: PCA9533D
• Description: 4-bit I2C LED dimmer
• Manufacturer: PHILIPS [NXP Semiconductors]

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 PCA9533/01
is shown in Figure 3 and PCA9533/02 in Figure 4.
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 PCA9533 which will be stored
in the Control Register.
The lowest 3 bits are used as a pointer to determine which register
will be accessed.
If the auto-increment flag is set, the three 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 ‘000’ 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
the input register (B2 B1 B0
Only the 3 least significant bits are affected by the AI flag.
Unused bits must be programmed with zeroes.
2004 Oct 01
4-bit I
RESET STATE: 00h
2
Figure 3. Slave address — PCA9533/01
Figure 4. Slave address — PCA9533/02
C LED dimmer
0
1
1
Figure 5. Control register
0
1
1
0
SLAVE ADDRESS
SLAVE ADDRESS
0
0
AUTO-INCREMENT FLAG
AI
0 0 0).
0
0
0
0
0
B2
1
1
REGISTER ADDRESS
0
1
B1
R/W
R/W
B0
SW01034
SW01037
SW01038
4
CONTROL REGISTER DEFINITION
REGISTER DESCRIPTION
INPUT — INPUT REGISTER
The INPUT register reflects the state of the device pins. Writes to
this register will be acknowledged but will have no effect.
NOTE: The default value “X” is determined by the externally applied
logic level, normally ‘1’ when used for directly driving LED with
pull-up to V
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
default
default
default
Default
B2
0
0
0
0
1
1
bit
bit
bit
bit
B1
0
0
1
1
0
0
DD
7
0
7
0
7
1
7
0
.
B0
0
1
0
1
0
1
6
0
6
0
6
0
6
0
REGISTER
NAME
INPUT
PWM0
PWM1
(PSC0
(PSC1
PSC0
PSC1
LS0
5
0
5
0
5
0
5
0
152
152
256
4
0
4
0
4
0
4
0
1)
1)
WRITE
WRITE
WRITE
WRITE
WRITE
READ/
READ/
READ/
READ/
READ/
READ
TYPE
LED
X
3
3
3
0
3
0
3
0
LED
PCA9533
X
LED SELECTOR
2
2
2
0
2
0
2
0
Product data sheet
PRESCALER 0
PRESCALER 1
FREQUENCY
FREQUENCY
REGISTER 0
REGISTER 1
REGISTER
FUNCTION
REGISTER
INPUT
PWM
PWM
LED
1
1
X
1
0
1
0
1
0
LED
0
0
X
0
0
0
0
0
0