CS5101A CS5102A
4.6.2 Register Burst Transmission (RBT)
RBT mode is selected by tying SCKMOD high, and
OUTMOD low. As in PDT mode, SCLK is an input,
however data is available immediately following
conversion, and may be clocked out the moment
TRK1 or TRK2 falls. The falling edge of HOLD
clears the output buffer, so any unread data will be
lost. A new conversion may be initiated before all
the data has been clocked out if the unread data
bits are not important (Figure 6).
4.6.3 Synchronous Self-clocking (SSC)
SSC mode is selected by tying SCKMOD low, and
OUTMOD high. In SSC mode, SCLK is an output,
and will clock out each bit of the data as it's being
converted. SCLK will remain high between conver-
sions, and run at a rate of 1/4 the master clock
speed for 16 low pulses during conversion
(Figure 7).
The SSH/SDL goes low coincident with the first
falling edge of SCLK, and returns high 2 CLKIN cy-
cles after the last rising edge of SCLK. This signal
frames the 16 data bits and is useful for interfacing
to shift registers (e.g. 74HC595) or to DSP serial
ports.
4.6.4 Free Run (FRN)
Free Run is the internal, synchronous loopback
mode. FRN mode is selected by tying SCKMOD
and OUTMOD low. SCLK is an output, and oper-
ates exactly the same as in the SSC mode. In Free
Run mode, the converter initiates a new conver-
sion every 80 master clock cycles, and alternates
between channel 1 and channel 2. HOLD is dis-
abled, and should be tied to either VD+ or DGND.
CH1/2 is an output, and will change at the start of
each new conversion cycle, indicating which chan-
nel will be tracked after the current conversion is
finished (Figure 8).
The SSH/SDL goes low coincident with the first
falling edge of SCLK, and returns high 2 CLKIN cy-
cles after the last rising edge of SCLK. This signal
frames the 16 data bits and is useful for interfacing
to shift registers (e.g. 74HC595) or to DSP serial
ports.
0
4
8
60 64
68
72
76
CLKIN (i)
HOLD (i)
C H1/2 (i)
Internal
S ta tu s
C onverting C h. 2
Tracking Ch. 1
SCLK (i)
SDATA (o) D15 D14
D1 D0 (Ch. 1)
SSH/SDL (o)
TRK1 (o)
TRK2 (o)
0
4
8
60 64 68 72 76
Converting Ch. 1
Tracking Ch. 2
D15 D14
D1
D0 (C h. 2)
0
D15
Figure 5. Pipelined Data Transmission (PDT) Mode Timing
20
DS45F6