pca9554ad NXP Semiconductors, pca9554ad Datasheet - Page 6

• Manufacturer Part Number: pca9554ad
• Description: 8-bit I2c And Smbus I/o Port With Interrupt
• Manufacturer: NXP Semiconductors

NXP Semiconductors
6. Functional description
PCA9554_9554A_7
Product data sheet
6.1.1 Command byte
5.2 Pin description
6.1 Registers
Table 2.
[1]
Refer to
Table 3.
The command byte is the first byte to follow the address byte during a write transmission.
It is used as a pointer to determine which of the following registers will be written or read.
Symbol
A0
A1
A2
IO0
IO1
IO2
IO3
V
IO4
IO5
IO6
IO7
INT
SCL
SDA
V
n.c.
Command
0
1
2
3
SS
DD
HVQFN package die supply ground is connected to both V
connected to supply ground for proper device operation. For enhanced thermal, electrical, and board level
performance, the exposed pad needs to be soldered to the board using a corresponding thermal pad on the
board and for proper heat conduction through the board, thermal vias need to be incorporated in the PCB in
the thermal pad region.
Figure 1 “Block diagram of
Pin
DIP16, SO16,
SSOP16, TSSOP16
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
-
Pin description
Command byte
Protocol
read byte
read/write byte
read/write byte
read/write byte
Rev. 07 — 13 November 2006
HVQFN16 SSOP20
15
16
1
2
3
4
5
6
7
8
9
10
11
12
13
14
-
[1]
Function
Input Port register
Output Port register
Polarity Inversion register
Configuration register
PCA9554/PCA9554A”.
8-bit I
6
7
9
10
11
12
14
15
16
17
19
20
1
2
4
5
3, 8, 13, 18
2
PCA9554/PCA9554A
C-bus and SMBus I/O port with interrupt
SS
pin and exposed center pad. V
Description
address input 0
address input 1
address input 2
input/output 0
input/output 1
input/output 2
input/output 3
supply ground
input/output 4
input/output 5
input/output 6
input/output 7
interrupt output (open-drain)
serial clock line
serial data line
supply voltage
not connected
© NXP B.V. 2006. All rights reserved.
SS
pin must be
6 of 30