LMH6521 Datasheet, PDF (17/24 Pages) Texas Instruments – LMH6521 High Performance Dual DVGA

FIGURE 10. Serial Interface Protocol (SPI compatible)
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R/Wb
Read / Write bit. A value of 1 indicates a read
operation, while a value of 0 indicates a write
operation.
Reserved Not used. Must be set to 0.
ADDR: Address of register to be read or written.
DATA In a write operation the value of this field will be
written to the addressed register when the chip
select pin is deasserted. In a read operation this
field is ignored.
C7
0= write
1=read
Serial Word Format for LMH6521
C6 C5 C4 C3 C2 C1 C0
0 0 0 0 0 0 0=Ch A
1=Ch B
Serial Word Format for LMH6521 (cont)
Enable Gb5 Gb4 Gb3 Gb2 Gb1 Gb0 RES
0=Off 1= 1= 1= 1= 1= 1=
0
1=On +16dB +8dB +4dB +2dB +1dB +0.5dB
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30120182
FIGURE 11. Serial Mode 4–wire Connection
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