Datasheet

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SLAS400B − SEPTEMBER 2003 − REVISED NOVEMBER 2005
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10
D11−4 & D3−0 D3−0
Conversion No N
Data For Conv. N
Data For Conv. N−1
CS
CONVST
BUSY
D11−D0
t
d1
+ t
(acq)
BYTE
t
2
t
d10
t
d7
t
d8
t
d2
Figure 6. Read Control Via CS and RD Tied to BDGND
DEVICE OPERATION AND DATA READ IN BACK-TO-BACK CONVERSION
The following two figures illustrate device operation in back-to-back conversion mode. It is possible to operate
the device at any throughput in this mode, but this is the only mode in which the device can be operated at
throughputs exceeding 3.5 MSPS.
A conversion starts on the CONVST falling edge. The BUSY output goes high after a delay (t
d2
). Note that care
must be taken not to abort the conversion (see Figure 4) apart from timing restrictions shown in Figure 7 and
Figure 8. The conversion ends within the conversion time, t
(conv)
, after the CONVST falling edge. The new
acquisition can be immediately started without waiting for the BUSY signal to go low. This can be ensured with
a CONVST high pulse width that is more than or equal to (t
0
– t
(conv)
+ 10 nsec) which is t
w4
for a 4-MHz operation.
Sample N
Conversion N
Data For Conversion N−1
(Data read Without Latency)
CONVST
BUSY
D11−D0
t
(conv)
+ t
d11
t
w4
t
w5
t
(acq)
t
d12
t0 = 250 ns for 4 MSPS Operation
Figure 7. Back-To-Back Operation With CS and RD Low