APEX MICROTECHNOLOGY CORPORATION • TELEPHONE (520) 690-8600 • FAX (520) 888-3329 • ORDERS (520) 690-8601 • EMAIL prodlit@apexmicrotech.com
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INTRODUCTION
This easy-to-use kit provides a platform for the evaluation
of linear power amplifiers circuits using the PA91 pin-out. With
ample breadboarding areas it is flexible enough to analyze a
multitude of standard or proprietary circuit configurations. Criti-
cal connections for power supply bypassing, compensation and
current limiting are pre-wired. Components not usually readily
available in engineering labs are provided. External connection
to the evaluation kit can be made via the terminals at the edge
of the circuit board. These terminal pads are suitable for stan-
dard banana jacks or direct soldering of wires. The schematic
is shown in Figure 1.
PARTS LIST
Part # Description, Vendor Quantity
HS27 Heatsink, Apex 1
EVAL24 PC Board, Apex 1
TW07 Thermal Washer, Apex 1 box, 10 ea.
P6KE250A Transient Zener, 2
Microsemi (250V)
CDC01 Capacitor .01µF 1kV, 2
Sprague 5GAS10
ASSEMBLY
1. See Figure 2. Insert and solder the transient zener diodes
at D3 and D4 (250V).
2. Insert and solder the disc bypass capacitors at C1 and C2.
3. Insert the HS27 heatsink and solder the solderable studs
from the opposite side of the PCB.
FIGURE 1.
Figure 1 shows the schematic of the
evaluation kit's pre-wired connections.
Components supplied with the kit are
marked with an asterisk (*). See the
amplifier's data sheet for full application
information.
4. Add banana jacks as necessary to complete connections to
external circuits and power supplies.
5. Insert the amplifier into the PCB mounting holes located in
the space between the heatsink fins. So not solder the pins
at this time.
6. Hang the TW07 thermal washer near the end of a 6-32 X
3/8" screw. Slightly pull the amplifier away from the heat sink
face. Use the screw to position the thermal washer behind
the amplifier and insert the screw into the mounting hole of
the heatsink. Use a 6-32 nut to secure the screw from the
opposite side of the heatsink. It is important that the entire
back surface of the amplifiers mounting tab be in contact
with the heatsink. Adjust the amplifiers position and tighten
the mounting screw as necessary for this to be so.
7. Solder the amplifiers pins to the PCB.
8. Add other passive components as necessary to complete
your circuit.
9. Most common configurations will ground the non-inverting pin
of the amplifier. J1 is a convenient way to do this if necessary
for your application circuit.
10. The four holes at the corners of the circuit board are for
mounting #6 standoff spacers if desired.
11. R1-R3 are multiple feedback resistors in series. Commonly
available resistors do not have a breakdown voltage sufficient
to stand off the output voltage of the amplifier. Using multiple
resistors will divide down the voltage that each resistor must
withstand.
APEX MICROTECHNOLOGY CORPORATION • 5980 NORTH SHANNON ROAD • TUCSON, ARIZONA 85741 • USA • APPLICATIONS HOTLINE: 1 (800) 546-2739
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EK11 EVALUATION KIT
FOR PA90, PA91, PA98 PIN-OUT
This data sheet has been carefully checked and is believed to be reliable, however, no responsibility is assumed for possible inaccuracies or omissions. All specifications are subject to change without notice.
EK11U REV D OCTOBER 2004 © 2004 Apex Microtechnology Corp.
FIGURE 2. PCB
