SU531273A1 - Device for automatic calibration of analog-digital converters - Google Patents

Description

(54) DEVICE FOR AUTOMATIC TESTING OF ANALOG-DIGITAL CONVERTERS

:.,; v. ; jc7i: 4 lux of automatic calibration:;: - logo-digital conversion of the contents of the digital-to-analog converter 1,; -io-:: the 2 voltage amplifier during the digital-to-analog converter 3, key 4, .examined analog - digital converter o, arithmetic unit 6, pulse length meter 6. Digital to analog converter 1 contains a digital setpoint device 8, converter 9 under voltage. The voltage converter 2 at a time comprises a linear voltage generator 10, comparison elements 11 and 12, and a trigger 13.

The digital-to-analog converter 3 consists of an adder 14, a code-to-voltage converter 15, and devices 16 for setpoint digital settings. The meter 7 contains a trigger i7, a match element 18, a device 19 for measuring time intervals.

The device works as follows.

Device 8 records the code value corresponding to the selected point in the range of variation of the input signal. The recorded code is fed to the input of the converter 9 and is converted to the appropriate voltage level U, in addition, the code from device 8 is fed to one input of the arithmetic device 6, to the other input of which the output of the converter 5 is connected

In device 16, a code is written that corresponds to the difference in voltage levels and 2 A, which converts to the corresponding voltage in converter 1 From the output of generator 9, If voltage goes to comparison element 11, key 4, summed up on adder 14 The output from the converter output: 15 is fed to one input of the element

Comparison 12. The other inputs of the elements of Comparison 11 and 12 are supplied linearly on the icicraiomee voltage from the output of the generator 10.

Om; time of i equality of the linear at the voltage and voltage level);) th –i -1leme ;; t comparison 11 expressions .iTf.maeT signal, flip-flop 13, which opens the key 4 The output from the converter under study 5. At the time t, the ramp voltage becomes equal to the voltage (2. This causes the comparison element 12 which pushes the PT to return the trigger 13 to its initial state, and the key 4 closes,

During time i, the converter 8 converts the voltage U: its corresponding code (N), which goes to the arithmetic unit 6 and

compared with a code ((Q) corresponding to exemplary voltage U.

If the time interval is less than the conversion time studied by the converter, then it will turn out to be ± 1, where U. is the tolerance on the systematic component of the total error of the converter 5.

The arithmetic unit 6 generates a mismatch pulse, which enters the digital setpoint device 16 and increases the setpoint code by a predetermined amount.

The measurement process is repeated until it turns out that K Mc ± d. The arithmetic unit 6 processes the digital setpoint code and the code from the output of the converter 5. The difference is the static error of the conversion.

In this case, the arithmetic unit 6 generates a coincidence pulse, which throws the trigger 17, allowing the gates with the duration i t about i equal conversion time to pass through the element 18 from the trigger 13 to the device 19.

If time i –p, - i is less than the conversion time, then it does not have time to correctly convert the input voltage and device 6 will give a pulse, flip-flop trigger 17, which prohibits the passage of strobe pulses into device 19.

Claims (1)

1. Copyright sovitelstvo USSR .- Avtosnyi sn;: 223474. MKI H 03 K 13 / 02.02.08 3190О5. l1k .; g ;.type of). / Oj