AD7277BRM AD [Analog Devices], AD7277BRM Datasheet - Page 19

• Manufacturer Part Number: AD7277BRM
• Description: 3MSPS,12-/10-/8-Bit ADCs in 6-Lead TSOT
• Manufacturer: AD [Analog Devices]

AD7278 in a 10 SCLK’s cycle Serial Interface
For the AD7278, if CS is brought high in the 10th rising
edge after the 2 leading zeros and the 8 bits of the
conversion have been provided, the part can achieve a
4.2MSPS throughput rate. For the AD7278, the track and
hold goes back into track in the 9th rising edge. In that
case, a f
gives a cycle time of t
With t
This TBDns satisfies the requirement of 50 ns for t
REV. PrF
Preliminary Technical Data
2
SDATA
SDATA
SCLK
SCLK
= TBDns min, this leaves t
&6
SCLK
&6
THREE-
STATE
= 52 MHz and a throughput of 4.2MSPS,
THREE-
STATE
SDATA
SCLK
&6
t
2
t
Z
2
2 LEADI NG
t
Z
2 LEADI NG
3
ZERO’S
t
2
3-STATE
1
3
ZERO’S
1
+ 8.5(1/f
ZERO
ZERO
t
2
2
2 LEADING ZERO’S
Z
2
PRELIMINARY TECHNICAL DATA
DB9
1
DB7
SCLK
ZERO
ACQ
Figure 19. AD7278 in a 10 SCLK Cycle Serial Interface
3
) + t
Figure 17. AD7277 Serial Interface Timing Diagram
3
t
t
Figure 18. AD7278 Serial Interface Timing Diagram
convert
4
DB8
t
t
2
4
convert
DB6
to be TBDns.
DB7
ACQ
4
t
5
4
t
5
3
= 238ns.
DB6
10
8
8.5 (1/ fSCLK)
DB1
ACQ
t
4
DB1
convert
t
6
DB5
.
1/ THROUGHPUT
t
11
6
1/ THROUGHPUT
9
1/ THROUGHPUT
DB0
–19–
B
5
DB0
B
From Figure 19, t
t
TBDns for t
TBDns.
12
QUIET
10
ZERO
ZERO
t
6
, where t
DB1
13
11
4TRAILING ZERO’S
6TRAILING ZERO’S
ZERO
9
t
B
7
t
7
DB0
QUIET
t
8
14
8
14
ZERO
= TBDns max. This allows a value of
ZERO
10
ACQ
satisfying the minimum requirement of
15
AD7276/AD7277/AD7278
3-STATE
15
comprises of 0.5(1/f
ZERO
ZERO
t
t
8
ACQ
t
8
t
QUIET
t
16
1
16
THREE-STATE
THREE-STATE
t
1
t
t
quiet
1
t
q uiet
SCLK
) + t
8
+