AD7945 Analog Devices, AD7945 Datasheet - Page 5

• Manufacturer Part Number: AD7945
• Description: +3.3 V/+5 V Multiplying 12-Bit DAC With a Parallel Interface
• Manufacturer: Analog Devices

Specifications of AD7945

• Resolution (bits): 12bit
• Dac Update Rate: 1.7MSPS
• Dac Settling Time: 600ns
• Max Pos Supply (v): +5.5V
• Single-supply: Yes
• Dac Type: Current Out
• Dac Input Format: Par

REV. B
AD7943 TIMING SPECIFICATIONS
Parameter
t
t
t
t
t
t
t
t
NOTES
1
2
3
Specifications subject to change without notice.
STB
DS
DH
SRI
LD
CLR
ASB
SV
All input signals are specified with tr = tf = 5 ns (10% to 90% of 5 V) and timed from a voltage level of 1.6 V. tr and tf should not exceed 1 s on any digital input.
STB mark/space ratio range is 60/40 to 40/60.
t
SV
3
is measured with the load circuit of Figure 2 and defined as the time required for the output to cross 0.8 V or 2.4 V.
2
STB1,
STB2,
STB4
STB3
LD1,
LD2,
CLR
SRO
SRI
t
DB11(N)
DS
(MSB)
t
SRI
Limit @
V
60
15
35
55
55
55
0
60
t
DH
DD
t
STB
= +3 V to +3.6 V
DB10(N–1)
DB10(N)
t
SV
Figure 2. Load Circuit for Digital Output Timing Specifications
Limit @
V
40
10
25
35
35
35
0
35
DD
TO OUTPUT
Figure 1. AD7943 Timing Diagram
= +4.5 V to +5.5 V
1
PIN
(T
A
= T
50pF
MIN
C
L
to T
1.6mA
200 A
–5–
MAX
, unless otherwise noted)
I
I
OL
OH
Units
ns min
ns min
ns min
ns min
ns min
ns min
ns min
ns max
+2.1V
Description
Min Time Between Strobing Input Shift
Register and Loading DAC Register
STB Pulsewidth
Data Setup Time
Data Hold Time
SRI Data Pulsewidth
Load Pulsewidth
CLR Pulsewidth
STB Clocking Edge to SRO Data Valid Delay
AD7943/AD7945/AD7948
DB0(N)
DB0(N–1)
t
ASB
t
LD ,
t
CLR