HI5731-EVS Intersil, HI5731-EVS Datasheet - Page 3

• Manufacturer Part Number: HI5731-EVS
• Description: EVALUATION PLATFORM SOIC HI5731
• Manufacturer: Intersil

Specifications of HI5731-EVS

• Number Of Dac's: 1
• Number Of Bits: 12
• Outputs And Type: 1, Differential
• Sampling Rate (per Second): 100M
• Data Interface: Parallel
• Settling Time: 20ns
• Dac Type: Current
• Voltage Supply Source: Analog and Digital, Dual ±
• Operating Temperature: -40°C ~ 85°C
• Utilized Ic / Part: HI5731
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Differential Linearity and Missing Codes
For a D/A Converter, the differential non-linearity is the worst
case deviation from the ideal step size throughout the entire
code range. For the HI5731, this worst case deviation is said
to be at most 1.0 LSB in magnitude. For any given D/A
converter, to guarantee no missing codes the converter must
be monotonic.
The definition of monotonicity is; as the input code is
increased the output should increase. When an input code is
increased and the output of the DAC does not increase or
reverses direction, then this converter is assumed to be non-
monotonic, or missing codes.
Monotonicity is guaranteed as long as a DNL value of
greater than -1.0 LSB is maintained.
Shown in Figure 6, as the input code increases the output
voltage should increase. When an error of greater than 1.0
LSB is incurred, that bit can be assumed to be a missing
code since the output did not increase but rather remained
the same.
-0.2
-0.4
-0.6
0.6
0.4
0.2
-0.2
-0.4
-0.6
0.8
0.6
0.4
0.2
0
0
FIGURE 5B. TYPICAL DNL PERFORMANCE CURVE
FIGURE 5A. INL TYPICAL PERFORMANCE CURVE
0
0
500
500
1000
1000
1500
1500
3-3
2000
CODE
2000
CODE
2500
2500
3000
3000
3500
3500
Application Note 9602
4000
4000
The Control Amplifier
The internal control amplifier converts the reference voltage
appearing on the REFOUT pin to a reference current via the
circuit shown in Figure 7A. The bias voltage generated at the
control amplifier output is used to mirror this current in all of
the precision current cells.
Adjusting Full Scale
The R
The output current is a function of the reference voltage
applied to the CONTROL AMP IN pin and the value of the
R
the following formula:
I
So where REF
and R
I
To adjust the output full scale current, use a potentiometer in
rheostat mode as shown in Figure 8B.
OUT
OUT
SET
FIGURE 7B. FULL SCALE OUTPUT APPLICATION CIRCUIT
11
10
01
00
Full Scale = 16 x (REF
= -20.62mA
SET
SET
resistor. To calculate the I
INPUT CODE GREATER THAN ZERO
REF
= 931
pin is used to set the Full Scale Output Current.
OUT
OUT
R
FIGURE 6. DNL EXAMPLE
SET
+
-
= -1.20V
(17)
FIGURE 7A.
-0.5 LSB ERROR
OUT
100
OUT
IN/R
Full Scale Current use
V
R
SET
EE
909
SET
(MISSING CODE)
)
CONTROL
AMP
GREATER THAN
-1.0 LSB
ERROR
OUT
OUTPUT
VOLTAGE