AD5520 datasheet(13/24 Pages) AD

13 / 24 page

AD5520

Rev. B | Page 13 of 24

THEORY OF OPERATION

The AD5520 is a single-channel per pin parametric measure-

ment unit (PPMU) for use in semiconductor automatic test

equipment. It contains programmable modes to force a pin

voltage and measure the corresponding current (FVMI), force

current measure voltage (FIMV), force current measure current

(FIMI), force voltage measure voltage (FVMV), and force

nothing measure voltage (FNMV). The PPMU can force or

measure a voltage from −11 V to +11 V. It can force or measure

currents up to 6 mA using the internal amplifier, while the

addition of an external amplifier enables higher current ranges.

External resistors allow users to choose the optimum ranges for

their needs.

The device provides a force sense capability to ensure accuracy

at the tester pin. A guard output is also available to drive the

shield of a force/sense pair.

The AD5520 has an on-board window comparator that

provides two bits of useful information, DUT too low or too

high. Also provided on the chip is clamp circuitry that flags via

CLHDETECT and CLLDETECT if the voltage applied to FIN

or across the DUT exceeds the voltage applied to CLL and CLH.

On-chip is clamp circuitry that clamps the output of the force

amplifier if the voltage at MEASIOUT and MEASVOUT

exceeds CLL or CLH.

AD5520 Datasheet(PDF) 13 Page - Analog Devices