Datasheet

ADP1650
Rev. C | Page 19 of 32
I
2
C INTERFACE
The ADP1650 includes an I
2
C-compatible serial interface for
control of the LED current, as well as for readback of system
status registers. The I
2
C chip address is 0x30 (0x60 in write
mode and 0x61 in read mode). Additional I
2
C addresses are
available on request.
Figure 42 illustrates the I
2
C write sequence to a single register.
The subaddress content selects which of the nine ADP1650
registers is written to. The ADP1650 sends an acknowledgment
to the master after the 8-bit data byte has been written. Figure 43
shows the I
2
C read sequence of a single register.
The register definitions are shown in the I
2
C Register Map
section.
SUBADDRESS
CHIP ADDRESS
01 100 00 0
00
0 = WRITE
0
A
DP1650 ACK
ADP1650 ACK ADP1650 ACK
ADP1650 RECEIVES
DATA
S
T
S
P
MASTER
STOP
08837-021
Figure 42. I
2
C Single Register Write Sequence
ADP1650 ACK ADP1650 ACK ADP1650 ACK
CHIP ADDRESS
011000 0 0
0
10
MASTER
STOP
CHIP ADDRESS
S
T
S
T
0110000 01 0
0 = WRITE 1 = READ
S
P
MASTER ACK
ADP1650 SENDS
DATA
SUBADDRESS
08837-020
Figure 43. I
2
C Single Register Read Sequence