SLWS132 Datasheet, PDF (16/46 Pages) Texas Instruments – QUAD RECEIVER CHIP

GC4014 QUAD RECEIVER CHIP
DATA SHEET REV 0.6
words will be transmitted immediately following the first I/Q pair as shown in Figure 10(c). Figure 10(c) also shows
how the RDY signal can be used to identify the I and Q channels in the TDM serial transmission.The bit-serial output
rate is programmable as a power-of-2 division of the input clock.
SCK
SFS
SOUT
clock stops after transfers are complete and stays low unless “continuous” is set
I15
I14
I1
I0
Q15 Q14
The words repeat in the continuous mode
I15
I14
Q1 Q0
(a) 16 BIT MODE, FRAME SYNC AT THE START OF EACH 16 BIT WORD
SCK
SFS
SOUT
clock stops after transfers are complete and stays low unless “continuous” is set
The words repeat in the continuous mode
I15
I14
I1
I0
Q15 Q14
I15
I14
Q1 Q0
(b) 32 BIT “PACKED” MODE, ONE FRAME SYNC AT THE START OF EACH 32 BIT TRANSFER
RDY
SFS
SOUT
SFS
SOUT
SFS
SOUT
RDY is 4 clocks wide (CK not SCK clocks) or is 16 clocks wide if RDY_WIDTH is set
IA
QA
Output Sample Period (OSP)
MUX_MODE=0
IA
QA
IA
QA IB
QB
MUX_MODE=1
IA
QA IB
QB
IA
QA IB
QB IC
MUX_MODE=2
QC ID
QD
IA
QA IB
QB
IC
QC
(c) ONE, TWO OR FOUR CHANNEL MUX MODES (PACKED MODE IS ON)
Figure 10. Serial Output Formats
The serial clock (SCK) will normally stop after the last bit transfer of each OSP. The user can force a
continuous clock by setting the CONTINUOUS control bit in the output control register. In the continuous mode the
data is repeated until the next OSP. This may be useful if the user wants to multiplex the outputs from multiple chips
onto the same serial bus. Note: The frame syncs are not intended to be used in the continuous mode. After the
proper number of frame syncs have been output as shown in Figure 10, the next frame sync will be missing in the
continuous mode. The frame syncs will then repeat every 16 (or 32 in the packed mode) bit clocks. Note also that
the number of bit clocks per output frame may not be a rational number, resulting in a truncated bit clock at the end
of the OSP.
3.6.3 Link Mode Output
The four serial output pins and the bit clock and frame sync pins can be configured as an ADSP-2106x
SHARC DSP chip link port. These pins are in a tri-state condition when the chip powers up. A control bit is set to
enable these pins and another control bit is set to enable the link port mode. In the link mode the READY output pin
becomes the ACK (acknowledge) input which is used to receive the link port “LACK” signal.
GRAYCHIP, INC.
- 11 -
APRIL 27, 1999
This document contains information which may be changed at any time without notice