ISL1561 Datasheet, PDF (10/13 Pages) Intersil Corporation – 3 pin serial port interface

ISL1561
General Description
The ISL1561 is a class G amplifier designed to reduce power
consumption in ADSL2+ and VDSL2 applications compared to
class AB. With the high PAR used for xDSL signals, a supply
voltage of +14V can be used for the majority of the small
amplitude cycles while boosting to a supply voltage of +28V can
be used for the few high amplitude cycles.
Digital Interface
A 12-bit serial port interface is used to program ISL1561. The
first bit defines the write (1’b1) and read (1’b0) operation to the
register. The following 3-bit calls the registers. The last 8-bit
programs the registers. Default start-up for ISL1561 is in disable
mode with boost and CS pins having internal pull ups and SCLK
and SDATA pins having internal pull downs. ISL1561 can only be
programmed through the SPI when CS is set low.
Register Listing
ADDRESS
FUNCTION
3’h3 Setting of quiescent current of port AB
3’h7 Setting of quiescent current of port CD
BIT
[7]
[6:0]
[7]
[6:0]
DESCRIPTION
Boost disable
Program quiescent current of port AB.
Boost disable
Program quiescent current of port CD.
0123
SCLK
Z-HI
W/R
SDATA
ADDR[0:2]
Z-HI
D[0] D[1] D[2] D[3] D[4] D[5] D[6] D[7]
CS
CURRENT SETTING VALUE
CS
SCLK
t_SC
t_SD
FIGURE 27. 12 BITS SERIAL ADDRESSING DIAGRAM
t_HC
t_SC
t
t_r
t_f
t_HD
t_w
SDATA
BN
B(N-1)
B(N-2)
B1
B0
t
LSB LOAD LSB FIRST, MSB LAST
MSB
FIGURE 28. 12 BITS SERIAL ADDRESSING DIAGRAM
10
FN7941.1
February 26, 2013