Datasheet

LT3746
14
3746fa
For more information www.linear.com/3746
operaTion
LDO
SCKO
SDO
CONTROLLER
LT3746 6-WIRE TOPOLOGY
SDI
SCKI
LDI
LDO
SCKO
SDO
LDI
SCKI
SDI
CHIP 1
LDO
SCKO
SDO
LDI
SCKI
SDI
CHIP 2
LDO
SCKO
SDO
LDI
SCKI
SDI
CHIP N
LDO
SCKO
SDO
CONTROLLER
CONVENTIONAL 4-WIRE TOPOLOGY
SDI
3746 F01
LDO
SCKO
SDO
LDI
SCKI
SDI
CHIP 1
LDO
SCKO
SDO
LDI
SCKI
SDI
CHIP 2
LDO
SCKO
SDO
LDI
SCKI
SDI
CHIP N
Figure 1. LT3746 6-Wire Topology vs Conventional 4-Wire Topology
COMMAND REGISTER:
C1: ENABLE LED CHANNELS - ENABLE = 1, DISABLE = 0
C0: FRAME SELECT - GS FRAME = 0, DC FRAME = 1
STATUS REGISTER:
S0-S31: LED 0-31 FAULT - FAULT = 1, OK = 0
F0: OT - OVER TEMPERATURE = 1, OK = 0
386 BITS
GS FRAMEGS 0, 12 BITS
DC 0, 6 BITSDC 31, 6 BITS
DC 0, 6 BITSDC 31, 6 BITS
3746 F02
GS 31, 12 BITS
LSB
LSB LSB
LSB
LSB
LSB
MSB MSB MSB MSB MSB MSB
C0C1
DC FRAMEC0C1x x x x x x
S00 0 0 0 0S31
0 0 0 0 0
x x x x x x
STATUS FRAME
F00
Figure 2. Serial Data Frame Format