ADS-112MC Murata Power Solutions Inc, ADS-112MC Datasheet - Page 4

• Manufacturer Part Number: ADS-112MC
• Description: Analog To Digital Converter
• Manufacturer: Murata Power Solutions Inc

CALIBRATION PROCEDURE
1. Connect the converter per Figures 3 and 4 and Tables 1 and 3 for the
2. Zero Adjustments
3. Full-Scale Adjustment
appropriate input range. Apply a pulse of 150 nanoseconds to the START
CONVERT input (pin 16) at a rate of 250kHz. This rate is chosen to reduce
the fl icker if LED’s are used on the outputs for calibration purposes.
Apply a precision voltage reference source between the amplifi er’s analog
input and ground. Adjust the output of the reference source per Table 2.
For unipolar, adjust the zero trimming potentiometer so that the output
code fl ickers equally between 0000 0000 0000 and 0000 0000 0001 with
COMP BIN (pin 18) tied high (straight binary) or between 1111 1111 1111
and 1111 1111 1110 with pin 18 tied low (complementary binary).
For bipolar operation, adjust the potentiometer such that the code fl ick-
ers equally between 1000 0000 0000 and 1000 0000 0001 with pin 18
tied high (offset binary) or between 0111 1111 1111 and 0111 1111
1110 with pin 18 tied low (complementary offset binary).
Set the output of the voltage reference used in step 2 to the value shown
in Table 2. Adjust the gain trimming potentiometer so that the output
code fl ickers equally between 1111 1111 1110 and 1111 1111 1111 for
pin 18 tied high or between 0000 0000 0001 and 0000 0000 0000 for
pin 18 tied low.
To confi rm proper operation of the device, vary the precision reference
voltage source to obtain the output coding listed in Table 4.
Input Range
0 to +10V
±5v
Table 1. Input Range Selection
OPERATION
BIPOLAR
21
20
Input Pin
Pin 19
Pin 19
+15V
–15V
+5V
4.7—F
4.7—F
4.7—F
0.1—F
www.murata-ps.com
OPERATION
UNIPOLAR
+
+
+
Pin 20 to Ground
Pin 20 to Pin 21
Tie Together
0.1—F
0.1—F
4.7—F
0.1—F
+
Figure 3. Typical ADS-112 Connection Diagram
20
24
23
21 +10V REF.
22
14
13
Note: Always bypass pin 21 to ground
ADS-112
12-Bit, 1MHz, Low-Power Sampling A/D Converters
COMP BIN
0 to +2.5V, ±1.25V
SIGNAL
INPUT
0 to 5V, ±2.5V
Input Range
Input Range
0 to 10V, ±5
0 to +10V
±5V
Table 3. Input Range (using external calibration)
18
Technical enquiries email: [e-mail], tel:
Figure 4. Optional Calibration Circuit
5k
R1
ADJUST
Table 2. Zero and Gain Adjust
For values of R1 and R2 refer to Table 3.
12
11
10
15
17
16
19
GAIN
9
8
7
6
5
4
3
2
1
50
5k
+5V
BIT 1 (MSB)
BIT 2
BIT 3
BIT 4
BIT 5
BIT 6
BIT 7
BIT 8
BIT 9
BIT 10
BIT 11
BIT 12 (LSB)
EOC
ENABLE (1-12)
START CONVERT
ANALOG INPUT
R1
2
2
2
Zero Adjust
+1/2 LSB
+1.22mV
+1.22mV
OFFSET
ADJUST
R2
14
2
6
ZERO/
+15V
10k
R2
–15V
MDA_ADS-112.B01 Page 4 of 6
+FS – 1 1/2 LSB
Gain Adjust
+9.9963V
+4.9963V
ADS-112
Unit
kW
kW
kW
To Pin19
of ADS-112
[phone]