Model 2210 System Facility Requirements The system requires a precision reference and a noise free power mains connection. Precision Reference Frequency:A 10MHz refer- ence frequency standard is required for the system. This
standard must be maintained to provide a 10 part per billion
accuracy per year. The signal must be jitter free. The signal
can be a 1V to 5V Peak To Peak Sine or Square Wave into a 50
load. Electrical Mains Supply:195 to 240VAC (220VAC nominal phase to phase and 115VAC phase to neutral), 50
Amps 3 phase, 50/60Hz is required for a complete system.
The mains feeder is a single connection to the PRA system
power distribution box. All measurement equipment is
powered via an isolation transformer that operates from
220VAC. A safety ground must also be provided. Equipment List These are the overall items that constitute a typical most capable version of the Model 2210 Testing System. Special application items
must be ordered individually.
Qty Description --- -------------------------------------------------- 2 PRA Equipment Bays, 1 with Power Distribution box 1 Set of PRA cabling (all needed cabling to connect the system together) 1 System software (backup software supplied on CD-ROM) 1 HP LaserJet printer 1 Counter: GT654, GT200, HP53131, HP53132 or HP53181 2 Controlling Computers, Pentium class systems (clock frequency to be 333MHz or greater, Windows 95/98. Computer #1: Controls the measurements Computer #2: User input/output, operates the printer, performs data reduction. 2 100baseT Ethernet cards and interconnect cables (used to permit the computers to communicate) 1 Arbor Press assembly to mate the pallet to the multiplexer 1 VCXO/TCXO Test Interface to the Chamber Includes the drive for the Voltage Control input of the VCXOs, multiplexer control signal buffers, RF output multiplexers, etc. 2 PRA Model 66222x Test Chambers 2 HP6652A Power Supply (0-20V 25A maximum) 8 DUT Pallets (4 used per chamber) 8 Multiplexer Assembly (4 used per chamber) A lower cost version only has one chamber, one computer and supports only half the number of parts. already stored on the computer with the proper temperature
points and soak times).
4. Prompts the operator to verify the master pallets are all
loaded into the chamber and if the operator is ready to begin
the run. (A yes starts the run).
5. All measurements now proceed automatically.
6. When the measurements are finished the system will
transfer all data to computer #2. All bad positions will be
listed (optionally the good location information can be
printed).
7. The chamber can now be reloaded and another
measurement run started. During operation, computer #1’s display shows the
status of both chambers. Plus it also displays the DUT
measurement information of the selected chamber. The
display is intended to be informational only. Each chamber in the system operates indepen- dently. The chambers may be started at different times and be
asked to do different measurement sequences (different
temperatures). Different temperature tests can be run on
individual chambers. Interleaving runs is possible and the
controlling computer optimizes all the combinations of runs
to minimize the total test time. System Appearance:The system is supplied on 2 movable chassis. Cryogenic fluid must be connected to each
chamber. Electrical power must be connected to the power
box on one chassis. In the event that electrical refrigeration is requested, the
chambers must be connected to the compressor assembly.
The compressors can be up to 3 meters from the actual test
system. This permits the noise and heat generated by the
compressors to be placed in a sheltered but exterior location.
A 10 meter hose option is also available. NOTE: PRA Inc. reserves the right to make changes to the product contained in this data sheet in order to improve the
design or performance and to supply the best possible product. PRA Inc. reserves the right to make these changes without
notice. Revised 9/1/02
System Configuration Multiplexer Control Signals: The multiplexer control signals are 11 parallel lines of TTL/HCMOS
compatible signals. This permits the 1 each individual DUT
of 3560 in the system be selected, (for pallets with reduced
DUT counts of less than 256, only part of the signals are
used). The signals are derived from a parallel I/O expansion
card plugged into the computer's ISA bus slot. Another
multiplex line enables the RTD multiplexer for calibration
purposes. Counter:The system can support several counter types, all are period or reciprocal type counters to provide
very fast measurements. HP and Guide Technology counters
are supported. Oscillator Under Test Power Supply: The power supply is an HP GPIB programmable power supply. The
supply is capable of 20VDC maximum and is rated to 25A.
Each chamber can be at a different supply voltage. Each
oscillator can draw up to 24mA each. Oscillator Under Test Vcontrol: The system is configured with a single isolated programmable Digital to
Analog Converter. The signal is floating to minimize any
grounding problems when the signal is
connected to each temperature chamber. This
signal is buffered on each multiplexer with
operational amplifiers before driving the
VcTCXO under test. The Vcontrol voltage can
be set to 5mV accuracy (0.025% of full scale). System Computers: The system is supplied with two computers. The IBM™
Compatible PCs are selected to be identical and
will be loaded with identical software. This
provides redundancy in case of computer
failure, the system could continue to operate at
20% to 50% of capacity on only one computer.
The 2 computers will be connected together
using the MicroSoft network functions of
Windows 95/98, Ethernet 100baseT interface
cards, and cables supplied with the system.
These computers can be integrated into a larger
peer to peer network or one with a Windows NT
server very easily. Measurement Computer:The #1 com- puter is used to perform the measurement
function. Because of the speed of measurement
and the need for measurement efficiency a
single computer is dedicated to this function.
Computer #1 will contain a GT654 Time Interval
Analyzer and 2 each parallel I/O cards. Each
card is inserted into an ISA bus slot.
Computer #1 will receive, from Computer #2, control files
which indicate what measurements to begin executing.
PRA’s supplied software permits the interaction of the 2
computers. When measurements are completed, the data will
be transferred to Computer #2. Data Computer:This computer is the user interface to the system. This computer prints device measurement
data and/or failed device information. It also starts new measurement functions, plus stores the measurement and
specification files. It also is the workstation upon which
entering, editing, or printing the measurement definition files
is executed. As a redundant option, the user can operate the
system from computer #2 but this will slow the measurement
function. This is not the mode intended for optimum system
throughput. System Operation: The operator begins the test process by loading and mating the pallets with the
multiplexer. These assemblies are inserted into the chamber.
Then the operator selects the correct options imbedded in
the software and the system is ready to test. The system is
menu driven. The screen prompts, operation and user
interface will that as defined for the PRA Model 2200 series
systems. The software is written in Visual BASIC for DOS
and source code is supplied with the system. A typical operation for one chamber is as follows
with the user control from computer #2. Each master pallet
assembly has the PRA auto reading serialization and the test
requirements have been previously entered into the data
base on Computer #2 for that serial number. The data entry was accomplished in a previous time while the systems were
operating and affords a much lower stress level, (and more
accurate data input), for the operator. The measurement
computer display will show:
1. Which chamber is to be measured.
2. Select the positions in the chamber to measure and what
are the specified limits. (The limits are obtained from a
specification file already on the computer’s hard disk).
3. Select the desired temperature measurement steps (a file is
Model 2210 System
The oscillator multiplexer requires greater than 0.2V
PP input in the range of 0.1Hz to 1GHz. Each oscillator output
is buffered (optionally prescaled) and then multiplexed to the
edge of each measurement board. The multiplexer board has locating pins to align the
pogo pin contacts with the oscillators in the pallets. Each oscillator Vcc lead is bypassed at the test
position and typically 10 ohm resistor is placed in series with
the Vcc supply to increase the isolation and perform the
supply current sensing function. Oscillator testing: The force of the pogo pins (4 contacts per DUT) is 0.34Kg (0.75 pound) per oscillator.
Compressing a full pallet of 256 devices requires 87.3Kg (192
pounds) of force. Once compressed, the assembly must be
held together in this configuration. A press with the proper alignment guides is
provided with the system. The
pallet is loaded with oscillators to
test, the multiplexer board, and
the locking bars are placed in the
press assembly. The arbor press handle is pulled down until a stop is reached, the locking bars are
slid to the locking position. Now,
the assembly is ready to place in
the chamber for testing. When testing is com-
pleted, the press is used to relieve
the tension on the locking bars.
The pallet and multiplexer assem-
bly can then be disassembled. Temperature Chamber The chamber used on the system is specifically designed to test small SMT parts. The chamber is designed
for stability and uniformity of temperature. The chamber has
minimal mass to enhance speed of change. See the data sheet
for the PRA Model 66222 chamber. Similar controllers,
identical control cabling, and identical system computer
control commands are used in most of the PRA chambers. The critical part of any rectangular chamber is to the
uniformity of temperature. The chamber must have the air
flow patterns optimized to correct for ‘down stream’ heating
from previous devices and shadowing the next DUT from the
air flow. Either of these conditions can perturb the individual
device temperature uniformity. The chamber internal square
corners create slower moving air streams and cause poor
circulating air flow. This also leads to non uniform
temperatures. For a specific type of cooling and DUT/pallet/
multiplexer configuration, the chamber can be optimized to provide good uniformity. This is done by adjusting the air
flow across each DUT. The air plenums and diverters work
together to distribute the air flow. (Special air plenums and air
diverter plates are designed as required by SMD device
load). The air diverter plates can be easily exchanged with
other units from the factory if the chamber needs to be used
for another type of test fixture. Chamber set point: User setting to 0.01oC resolution
User sets the new temperature and the slew rate to follow to
the new set temperature. Accuracy: Absolute: ±0.25oC Uniformity: ±0.50oC Stability: ±0.10oC Repeatability ±0.05oC
Multiplexers and Carrier Plates The carrier palletshold the DUT during testing and may also be used to hold the parts during bake out (aging),
room temperature testing, marking, and other operations.
The carrier pallet contains no electronics. The carrier pallets hold the parts in a 16 X 16 array
(256 UUTs). The UUTs are expected to be in the pallet with the contacts upwards. This loading effort can typically be
accomplished through the use of manual ‘flip transfer’
methods from other in pro-
cess carriers. The pallets are de-
signed to be stackable for
DUT storage purposes. The
outside guide holes are used
to align the pallet to the
measurement fixtures. The
pallet has wider spacing in
the center to increase the
strength and to permit space
for the clamping assembly
when the pallet is assembled
with the test circuit fixtures. The pallets are
made from aluminum and are
hard anodized. The pallets
are machined on a Numerical
Controlled (NC) 3 axis milling
center. Aluminum is selected
because of the excellent
thermal conductivity. PRA
can provide alternate materi-
als when high volumes of
parts are to be tested. The figures show
typical UUTs and the UUT positioning in the carrier plate. The carrier plate is unique for
each oscillator type. Oscillator measurements and
Electronic Multiplexing:The DUT is contacted by pogo pins. The pogo pins are mounted in a PCB that contains the
needed multiplexer circuits to permit the counter to read the
output waveform or frequency of each oscillator.
The 2210 system permits easy part handling of
surface mount (SMD) oscillators. The system is designed
around the use of an "X-Y" arrayed pallet that precisely holds
the SMD parts with the contacts up. The system can also test
smaller size leaded packaged parts. The surface mount pads on the surface mount de-
vices under test are probed with pogo pins located on a
product-oscillatortypeuniquemultiplexerprintedcircuitboard.
Careful design of the assembly and precision guide pins
assure the pallet and multiplexer have accurate pad to pin
alignment. This sandwiched assembly is inserted into a spe-
cially designed, compact, square temperature chamber. Each
chamber can hold up to 4 pallet arrays totalling 1024 units per
chamber. The system is capable of operating 2 chambers and
can test up to 2048 SMD parts per run. The PRA Model 66222 temperature chambers are
optimized to provide good
temperature uniformity for
the pallet/multiplexer as-
semblies. Printed circuit
boards are used through-
out the chamber for the
signal interconnect, instead
of cabling, improving the
reliability of the chamber
construction. The most capable
version of the system em-
ploys the use of 2 Ethernet
linked computers. One com-
puter makes the device
measurements and controls
the temperature chambers.
The other computer is used
for data reduction and
network functions. They
are both loaded with the
same software, and in emer-
gency, either can operate
the test system. The SMD devices
are placed in 4 special
pallets and combined with a
product specific electronic
multiplexer. This pallet style system permits the most
efficient handling of the surface mount parts while providing
the optimum ‘packing’ of the temperature chambers for more
parts per run. The pallet design also permits automated
loading and unloading of the SMD parts. A pallet and multiplexer is normally designed for
each product type. Small dimensional part variations often
require an adjustment in pallet and multiplexer dimensions to
provide the most accurate alignment of the pogo pins.
The PRA Model 2210 SMD crystal oscillator temperature
test system has been optimized to provide the best possible
throughput for surface mount devices. These features are: System Features The parts are arranged in a 16 by 16 DUT array per pallet for a total of 256 UUTs per carrier. The VCXO control voltage range is ±10V. The
maximum load per DUT input is 100uA. Frequency measurements are user setable, 0.1ppm
resolution is typically used. Resolution to 0.1ppb is
selectable. GO/NOGO testing is possible through 1GHz.
Frequency and current draw can be measured per oscillator.
GO/NOGO testing is also possible over entire frequency
range, while full waveform measurements are limited to
approximately 180MHz maximum. Cryogenic cooling will be supplied to perform cold
temperature testing. Either liquid nitrogen or liquid carbon
dioxide can be used. The cryogenically cooled chamber
temperature capability is from -65oC to +150oC, the full system range is limited to -55oC to +125oC unless special wide
temperature range multiplexers are supplied. Electrical cooling can be supplied, if required, but
the cooling rate will be slower than with the cryogenic
cooling options. System Throughput Considerations: The Model 2210, employing 4 runs from -35oC to +85oC in 10 steps over
an extended 8 hour shift can process more than 160,000 units
per month. This calculation includes a 10% overhead and
service time allowance.
Model 2210
Oscillator Temperature Test System Rectangular shaped chamber with a
special temperature equalized air
flow that tests up to 1024 oscillators
placed in 4 pallet carriers System ideally suited for
TCXO, VCXO and
TCVCXO testing Features: - Holds UUTs in a rectangular array pallet ideally
holding SMD units - UUT measurements to 1 GHz: Supply current Frequency Pullability - Electronic multiplexer
of the UUT signals. - Optional waveform
measurements to 180MHz - CO2, LN2 or
compressor cooled - Special air flow
control to each pallet
for excellent uniformity -Enhanced PID Controller - RS232 COM port
interface. Inter
chamber daisy chaining
of multiple chambers
by RS485.
