Datasheet
Table Of Contents
- 1. General description
- 2. Features and benefits
- 3. Applications
- 4. Ordering information
- 5. Block diagram
- 6. Pinning information
- 7. Functional description
- 7.1 Device address
- 7.2 Command register
- 7.3 Register definitions
- 7.4 Writing to port registers
- 7.5 Reading the port registers
- 7.5.1 Register 0 - Input port register
- 7.5.2 Register 1 - Polarity inversion register
- 7.5.3 Register 2 - Bus-hold/pull-up/pull-down enable register
- 7.5.4 Register 3 - Pull-up/pull-down selector register
- 7.5.5 Register 4 - Configuration register
- 7.5.6 Register 5 - Output port register
- 7.5.7 Register 6 - Interrupt mask register
- 7.5.8 Register 7 - Interrupt status register
- 7.6 Power-on reset
- 7.7 RESET input
- 7.8 Software reset
- 7.9 Interrupt output (INT)
- 7.10 Standby
- 8. Characteristics of the I2C-bus
- 9. Bus transactions
- 10. Application design-in information
- 11. Limiting values
- 12. Static characteristics
- 13. Dynamic characteristics
- 14. Test information
- 15. Package outline
- 16. Handling information
- 17. Soldering of SMD packages
- 18. Abbreviations
- 19. Revision history
- 20. Legal information
- 21. Contact information
- 22. Contents
PCA9574 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2014. All rights reserved.
Product data sheet Rev. 5 — 25 September 2014 22 of 32
NXP Semiconductors
PCA9574
8-bit I
2
C-bus and SMBus, level translating, low voltage GPIO
Fig 18. Definition of timing
t
SP
t
BUF
t
HD;STA
PP S
t
LOW
t
r
t
HD;DAT
t
f
t
HIGH
t
SU;DAT
t
SU;STA
Sr
t
HD;STA
t
SU;STO
SDA
SCL
002aaa986
0.7 × V
DD
0.3 × V
DD
0.7 × V
DD
0.3 × V
DD
Fig 19. Reset timing
SDA
SCL
002aad062
t
rst
50 %
30 %
50 % 50 %
50 %
t
rec(rst)
t
w(rst)
RESET
P0 to P7
output off
START
t
rst
ACK or read cycle