Datasheet

REV. A
AD7677
–16–
The BYTESWAP pin allows a glueless interface to an 8-bit bus.
As shown in Figure 16, the LSB byte is output on D[7:0] and
the MSB is output on D[15:8] when BYTESWAP is low. When
BYTESWAP is high, the LSB and MSB bytes are swapped and
the LSB is output on D[15:8] and the MSB is output on D[7:0].
By connecting BYTESWAP to an address line, the 16 bits of
data can be read in 2 bytes on either D[15:8] or D[7:0].
CS
RD
BYTE
PINS D[15:8]
PINS D[7:0]
HI-Z
HI-Z
HIGH BYTE LOW BYTE
LOW BYTE HIGH BYTE
HI-Z
HI-Z
t
12
t
12
t
13
Figure 16. 8-Bit Parallel Interface
t
3
BUSY
CS, RD
CNVST
SYNC
SCLK
SDOUT
123 141516
D15 D14 D2 D1 D0X
EXT/INT = 0
RDC/SDIN = 0 INVSCLK = INVSYNC = 0
t
14
t
20
t
15
t
16
t
22
t
23
t
29
t
28
t
18
t
19
t
21
t
30
t
25
t
24
t
26
t
27
Figure 17. Master Serial Data Timing for Reading (Read After Convert)
RDC/SDIN = 1 INVSCLK = INVSYNC = 0
D15 D14 D2 D1 D0X
123 141516
BUSY
SYNC
SCLK
SDOUT
CS, RD
CNVST
t
3
t
1
t
17
t
14
t
15
t
19
t
20
t
21
t
16
t
22
t
23
t
24
t
27
t
26
t
25
t
18
EXT/INT = 0
Figure 18. Master Serial Data Timing for Reading (Read Previous Conversion During Convert)