Product Specification

SP4280

Page 4 of 7

│

Evaluation Kit

The SPDT Switch Evaluation Kit board was

designed to ease customer evaluation of the

SP4280 SPDT switch. The RFC port is

connected through a 75

transmission line to J2.

Port 1 and Port 2 are connected through 75

transmission lines to J1 and J3. A through

transmission line connects F connectors J4 and

J5. This transmission line can be used to

estimate the loss of the PCB over the

environmental conditions being evaluated.

The board is constructed of a four metal layer

FR4 material with a total thickness of 0.062”. The

transmission lines were designed using a

coplanar waveguide with ground plane (28 mil

core, 21mil width, 30 mil gap).

J6 provides a means for controlling DC and digital

inputs to the device. The provided jumpers short

the package pin to ground for logic low. When

for logic high.

When the jumper is in place, 3 µA of current will

flow through the 1 M

pull up resistor. This extra

current should not be attributed to the

requirements of the device.

Proper PCB design is essential for full isolation

performance. This eval board demonstrates good

trace and ground management for minimum

coupling and radiation.

Figure 4. Evaluation Board Layouts

Figure 5. Evaluation Board Schematic

75 OHM T-Line

75 OHM T-Line

75 OHM T-Line

75 OHM T-Line

1

J5

J5

R1

1M

R1

1M

R2

1M

R2

1M

VDD

1

GND

3

VSS/GND

5

GND

7

GND

2

GND

4

GND

6

GND

8

GND

1 0

GND

1 2

GND

1 4

C2

13

C1

9

GND

11

J6

HEADER 7 X2

J6

HEADER 7 X2

1

J4

J4

1

J3

J3

C3

DNI

C3

DNI

GND

2

RF1

3

GND

4

GND

5

GND

1

GND

12

GND

11

RF2

13

GND

14

GND

15

GND

21

U1

PE4280

U1

PE4280

C1

DNI

C1

DNI

C2

DNI

C2

DNI

1

J2

J2

1

J1

J1

Tel: +86-23-62808818

Fax: +86-23-62805284

www.sipatsaw.com / sawmkt@sipat.com