EK27
EK27U Rev I
5
ASSEMBLY
During the assembly, please refer to the circuit schematics, assembly drawings, and the data sheet of the part
being used on the evaluation kit.
1. Note that each side of the circuit board is identified as either the component side or the DUT side. The
component side has the designators printed on that side.
2. All the components are installed on the component side of the board and soldered on the DUT side.
3. First mount diodes D1, D2 and resistors RFB1, RFB3 on the component side of the board.
4. A power DIP socket (MS05) is supplied with this kit. The MS05 socket incorporates two cavities to retain
the #6 x 1/4” nuts (90730A007). Insert one #6 nut into each cavity. Make sure the nuts are fully seated into
the cavities. Using #6 x 0.75" screws (91735A151) provided with the kit, mount the socket from the DUT
side of the board.
5. Attach the heat sink to the board from the DUT side, using #8 x 0.375" screws (91735A192). Refer to the
assembly drawings for the correct way to attach the heat sink. This is done to keep the socket tightly
mounted to the board and to provide support, and eliminate stress so that the socket pins do not move
while being soldered from the component side. Once the socket pins are soldered, and the socket is now
attached to the board, remove the heat sink and all the screws.
6. First install all the smaller components on the board. This is done because it becomes difficult to install a
smaller part on the board once all the larger components are installed.
7. In most applications, RISO-1 and RISO-2 will be shorted; use 2 pieces of 16 AWG wire (1.5mm) (not
included) to short RISO-1 and RISO-2.
8. Mount electrolytic capacitors CBP-1 and CBP-2 for PA50. Mount capacitors CBP-1’ and CBP-2’ for PA52.
9. Ensure that the orientation of the electrolytic capacitors and the diodes match the circuit schematic
drawing.
10. Mount the BNC connector provided with the kit (146510CJ) and solder it to the board. Also mount the
terminal strip (TSO2) provided in the kit. Refer to the assembly drawings before mounting the terminal
strip. Make sure the terminal strip sits flat against the circuit board.
11. #8 hex stand offs (91841A009) are also provided with the kit. Install the # 8 x 0.25"screws (91735A190),
provided with the kit, from the component side. Attach the standoffs to these screws on the corners of
the board. Refer to the assembly drawings while installing the standoffs.
12. Attach the heatsink as before in step 5. Cut the Teflon tubing into 12 pieces, each of length 0.21 inches or
5.33mm (1/5 of an inch) approximately. These pieces go onto the pins of the Power Amplifier before
inserting it into the socket. This is done to insulate the pins from the heat sink and make sure that the PA
is tightly fixed into the socket. An Exacto knife works well for this.
NOTE
: The Teflon pieces should not be longer than the suggested length. If the pieces are longer, they
may interfere in the seating of the part to the heat sink and create a gap between the heat sink and the
part body.
13. Ten thermal washers (TW05) are provided with the kit. The thermal washer is used between the part and
the heat sink. A new washer must be used for each mounting. Mount the Power amplifier to the socket
using the thermal washer provided with the kit. Secure with the #6 screws. Note, the pin closest to the
input resistors (RIN1 and RIN2) is the pin #1 of the amplifier.
14. Place jumpers J1 and J3 for a non-inverting amplifier. Connect X6 jumper.
15. Connect jumpers X9 and X10 to connect boost voltage and supply voltage.
16. Connect the external connections via the BNC connector and terminal strip. Hook up power supply and
signals as necessary. The amplifier is now ready for testing.
Figure 3 shows the schematic diagram for the assembled circuit.
