Datasheet

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SLAS400B − SEPTEMBER 2003 − REVISED NOVEMBER 2005
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9
CONVERSION ABORT
The falling edge of CS
aborts the conversion while BUSY is high and CONVST is high (see Figure 4). The device
outputs FE0 (hex) to indicate a conversion abort.
1111 1110 0000
t
d5
CS
CONVST
BUSY
t
su1
RD
D11−D0
Figure 4. Conversion Abort
DATA READ
Two conditions need to be satisfied for a read operation. Data appears on the D11 through D0 pins (with D11
MSB) when both CS and RD are low. Figure 5 and Figure 6 illustrate the device read operation. The bus is
three-stated if any one of the signals is high.
D11−4 & D3−0 D3−0
t
w5
CS
CONVST
BUSY
D11−D0
t
d2
t
d1
+ t
(acq)
t
(conv)
t
d11
t
d6
t
d7
t
d9
BYTE
t
1
RD
Figure 5. Read Control Via CS and RD
There are two output formats available. Twelve bit data appears on the bus during a read operation while BYTE
is low. When BYTE is high, the lower byte (D3 through D0 followed by all zeroes) appears on the data bus with
D3 in the MSB. This feature is useful for interfacing with eight bit microprocessors and microcontrollers.