GC5018 Datasheet, PDF (12/115 Pages) Texas Instruments – 8-CHANNEL WIDEBAND RECEIVER

GC5018
8-CHANNEL WIDEBAND RECEIVER
SLWS169 – MAY 2005
www.ti.com
The 23-bit LFSR output signal if used to create a 16-bit “dout(15:0)” test signal using XOR combinations of
the LFSR bits.
lfsr (22)
lfsr (20)
lfsr (22)
lfsr (16)
lfsr (22)
lfsr (15)
lfsr (22)
lfsr (14)
lfsr (22)
lfsr (13)
lfsr (22)
lfsr (12)
lfsr (22)
lfsr (11)
dout(15)
dout(14)
dout(13)
dout(12)
dout(11)
dout(10)
lfsr (19)
lfsr (18)
lfsr (17)
lfsr (16)
lfsr (15)
lfsr (14)
lfsr (13)
lfsr (12)
lfsr (11)
lfsr (10)
dout(9)
dout(8)
dout(7)
dout(6)
dout(5)
dout(4)
dout(3)
dout(2)
dout(1)
dout(0)
To enable the test signal generator, the slf_tst_ena control bit is set. The rxin_a/b/c/d signals will be then
replaced by the four generator output streams. To use this test signal generator as a signal source for self
test, the user must also set the adc_fifo_bypass control bit. Setting the adc_fifo_bypass control bit causes
the adcclk_a/b/c/d input clocks to be internally replaced with rxclk/N, where N is as programmed with the
rate_sel(1:0) control bits to {1,2,4 or 8}.
The test signal generators can also output a programmable constant value. All four test signal generators
output the same programmable constant value.
12
RECEIVE DIGITAL SIGNAL PROCESSING