Datasheet

PCA9570 All information provided in this document is subject to legal disclaimers. © NXP Semiconductors N.V. 2014. All rights reserved.
Product data sheet Rev. 4 — 17 September 2014 5 of 32
NXP Semiconductors
PCA9570
Remote 4-bit general purpose outputs for 1 MHz I
2
C-bus
7. Functional description
Refer to Figure 1 “Block diagram of PCA9570”.
7.1 Device address
Following a START condition, the bus master must send the address of the slave it is
accessing and the operation it wants to perform (read or write). The address of the
PCA9570 is 48h as shown in Figure 6
.
7.2 Software Reset Call, and device ID addresses
Two other different addresses can be sent to the device.
• General Call address: allows resetting the device through the I
2
C-bus upon reception
of the right I
2
C-bus sequence. See Section 7.2.1 “Software Reset” for more
information.
• Device ID address: allows reading ID information from the device (manufacturer, part
identification, revision). See Section 7.2.2 “
Device ID (PCA9570 ID field)” for more
information.
Fig 6. PCA9570 device address
R/W
002aag831
0 1 0 0 1 0 0
fixed
slave address
Fig 7. General Call address Fig 8. Device ID address
0
002aac115
0 0 0 0 0 0 0
R/W
R/W
002aac116
1 1 1 1 1 0 0