pca9501 NXP Semiconductors, pca9501 Datasheet - Page 5

• Manufacturer Part Number: pca9501
• Description: 8-bit I2c And Smbus I/o Port With Interrupt, 2-kbit Eeprom And 6 Address Pins
• Manufacturer: NXP Semiconductors

Philips Semiconductors
FUNCTIONAL DESCRIPTION
DEVICE ADDRESSING
Following a START condition the bus master must output the address of the slave it is accessing. The address of the PCA9501 is shown in
Figure 5. Internal pullup resistors are incorporated on the hardware selectable address pins.
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
The PCA9501 contains a single 8-bit register called the Control Register, which can be written and read via the I
after a successful acknowledgment of the slave address.
It contains the I/O operation information.
2004 Sep 30
8-bit I
2-kbit EEPROM and 6 address pins
(a) I/O EXPANDER
(b) MEMORY
2
C and SMBus I/O port with interrupt,
WRITE PULSE
DATA FROM
SHIFT REGISTER
POWER-ON
RESET
READ PULSE
DATA TO
SHIFT REGISTER
FIXED
0
A5
SLAVE ADDRESS
A4
PROGRAMMABLE
HARDWARE
A3
a.
Figure 4. Simplified schematic diagram of each I/O
A2
A1
D
C
I
Figure 5. PCA9501 slave addresses
FF
S
A0
Q
R/W
D
C
I
FF
S
Q
5
FIXED
1
100 A
A5
SLAVE ADDRESS
A4
PROGRAMMABLE
HARDWARE
A3
b.
A2
A1
A0
V
V
I/O0 TO I/O7
DD
SS
2
R/W
SW02006
C bus. This register is sent
TO INTERRUPT LOGIC
SW00788
PCA9501
Product data sheet