AD5520 Analog Devices, AD5520 Datasheet - Page 16

• Manufacturer Part Number: AD5520
• Description: Per Pin Parametric Measurement Unit/Source Measure Unit
• Manufacturer: Analog Devices

AD5520
TYPICAL APPLICATION CIRCUIT
Figure 9 shows the AD5520 as it would be used in an ATE
system. This device could be used as a per pin parametric unit
in order to speed up the rate at which testing could be done. It
could also be used as a DUT power supply, as shown in the
application circuit. The central PMU shown in the block
diagram is usually a highly accurate PMU and is shared among a
number of pins in the tester. In general, many discrete levels are
required in an ATE system for the pin drivers, comparators,
clamps, and active loads. DAC devices, such as the AD5379, offer
a highly integrated solution for a number of these levels. The
AD5379 is a dense 40-channel DAC designed with high channel
requirements, like ATE in mind.
The flexible function of the AD5520 also makes it suited for use in
instrumentation applications such as source measure units. Source
measure units are programmable instruments capable of sourcing
and measuring voltage or current simultaneously. The AD5520
provides a more integrated solution in such equipment.
EVALUATION BOARD FOR THE AD5520 PMU
A full featured evaluation kit is available for the AD5520. It
consists of an evaluation board with direct hookup via a 36-way
COMPARE
MEMORY
TIMING DATA
GENERATOR
DLL, LOGIC
MEMORY
TIMING
FORMATTER
DE-SKEW
FORMATTER
DE-SKEW
CENTRAL PMU
DAC
ADC
DAC
DAC
DAC
DAC
DAC
DAC
DAC
DAC
COMP
VCOM
GUARD AMP
IOL
IOH
DRIVER
VTERM
VH
Figure 9. Typical Application ATE Circuit
ACTIVE LOAD
VL
VTH
VTL
DAC
DAC
VCL
VCH
RELAYS
–16–
DAC
ADC
centronics connector to a PC. PC-based software to control the
AD5520 is provided as part of the evaluation kit. The evalua-
tion board schematic is shown in Figure 10. Note that V
V
voltage range. In addition to the supply voltages for the evalua-
tion board, it is also necessary to provide the following voltage
levels for the clamp, comparator, and the force input pin—CLL,
CLH, CPL, CPH, and FIN. SMB connections are provided
for these voltage inputs. To use the evaluation board, it will also
be necessary to provide a DUT connected via the gold pins.
Both AGND and DGND inputs are provided on the board.
The AGND and DGND planes are connected at one location
close to the AD5520. It is recommended not to connect AGND
and DGND elsewhere in the system to avoid ground loop prob-
lems. REFGND is routed back to AGND at the power block to
maintain a clean ground reference for accurate measurements.
Each supply is decoupled to the relevant ground plane with
10 F and 0.1 F capacitors. The device supply pin is again
decoupled with a 10 F and 0.1 F capacitor pair to the relevant
ground plane.
Care should be taken when replacing devices to ensure that
the pins line up correctly with the PCB pads.
PPMU
SS
must provide sufficient headroom for the force and measure
GND SENSE
50
COAX
DEVICE POWER
SUPPLIES
DEVICE UNDER
DAC
ADC
TEST (DUT)
GUARD
AMP
REV. A
DD
and