AD7226KRZ Analog Devices Inc, AD7226KRZ Datasheet - Page 11

• Manufacturer Part Number: AD7226KRZ
• Description: IC DAC 8BIT LC2MOS QUAD 20-SOIC
• Manufacturer: Analog Devices Inc

Specifications of AD7226KRZ

• Data Interface: Parallel
• Settling Time: 4µs
• Number Of Bits: 8
• Number Of Converters: 4
• Voltage Supply Source: Dual ±
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 20-SOIC (7.5mm Width)
• Resolution (bits): 8bit
• Sampling Rate: 143kSPS
• Input Channel Type: Parallel
• Supply Current: 13mA
• Digital Ic Case Style: SOIC
• No. Of Pins: 20
• Number Of Channels: 4
• Resolution: 8b
• Conversion Rate: 143KSPS
• Interface Type: Parallel
• Single Supply Voltage (typ): 15V
• Dual Supply Voltage (typ): -5/12/-5/15V
• Architecture: R-2R
• Power Supply Requirement: Single/Dual
• Output Type: Voltage
• Integral Nonlinearity Error: ±0.5LSB
• Single Supply Voltage (min): 14.25V
• Single Supply Voltage (max): 15.75V
• Dual Supply Voltage (min): -4.5/11.4V
• Dual Supply Voltage (max): -5.5/16.5V
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 20
• Package Type: SOIC W
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power Dissipation (max): -
• Lead Free Status / Rohs Status: Compliant

STAIRCASE WINDOW COMPARATOR
In many test systems, it is important to be able to determine
whether some parameter lies within defined limits. The staircase
window comparator of Figure 14a is a circuit that can be used,
for example, to measure the V
device under test. Upper and lower limits on both V
can be programmably set using the AD7226. Each adjacent pair
of comparators forms a window of programmable size. If V
lies within a window, then the output for that window will be
high. With a reference of 2.56 V applied to the V
minimum window size is 10 mV.
The circuit can easily be adapted to allow for overlapping of
windows as shown in Figure 15a. If the three outputs from this
circuit are decoded then five different nonoverlapping program-
mable windows can again be defined.
REV.
D
AD7226
AGND
V
V
V
V
V
REF
Figure 14a. Logic Level Measurement
OUT
OUT
OUT
OUT
A
B
C
D
Figure 14b. Window Structure
V
DD
V
V
V
V
OL
OH
OH
OL
V
V
V
V
AGND
OUT
OUT
OUT
OUT
(HIGH)
V
(LOW)
(LOW)
(HIGH)
REF
A
B
C
D
WINDOW 1
WINDOW 2
WINDOW 3
WINDOW 4
WINDOW 5
OH
FROM D.U.T.
V
TEST
and V
5V
5V
5V
5V
5V
OL
1/4 CA339
10k
10k
10k
10k
10k
thresholds of a TTL
REF
WINDOW 1
WINDOW 2
WINDOW 3
WINDOW 4
WINDOW 5
OH
input, the
and V
TEST
OL
–11–
VARYING REFERENCE SIGNAL
In some applications, it may be desirable to have a varying signal
applied to the reference input of the AD7226. The AD7226 has
multiplying capability within upper and lower limits of reference
voltage when operated with dual supplies. The upper and lower
limits are those required by the AD7226 to achieve its linearity
specification. Figure 16 shows a sine wave signal applied to the
reference input of the AD7226. For input signal frequencies up
to 50 kHz, the output distortion typically remains less than 0.1%.
Typical 3 dB bandwidth figure is 700 kHz.
+4V
–4V
* DIGITAL INPUTS OMITTED
FOR CLARITY
AD7226
AGND
V
REF
V
V
V
V
Figure 16. Varying Reference Signal
OUT
OUT
OUT
OUT
+15V
Figure 15a. Overlapping Windows
V
V
V
V
A
B
C
D
AGND
15k
10k
Figure 15b. Window Structure
OUT
OUT
OUT
OUT
V
V
REF
DD
B
A
D
C
WINDOW 2
V
FROM D.U.T.
TEST
DAC A
V
REF
AD7226
5V
5V
5V
V
SS
WINDOW 1
WINDOW 3
10k
10k
10k
AGND
*
AD7226
WINDOW 1
WINDOW 2
WINDOW 3
V
DGND
DD
V
OUT
A