Very Low Distortion Attenuator Plastic Packaged PIN Diodes

SMP1307 Series

Alpha Industries, Inc. [781] 935-5150

• Fax [617] 824-4579 • Email sales@alphaind.com • www.alphaind.com

3

Specifications subject to change without notice. 1/01A

SMP1307-027 4 Diode PI Attenuator

The SMP1307-027 employs 4 PIN diode junctions in a

5-lead SOT package. It is configured for ease of

insertion in the PI attenuator circuit commonly used for

broadband TV distribution systems, covering a frequency

range from 5 MHz to beyond 1 GHz.

A broadband attenuator was designed using the

SMP1307-027 showing good performance to 2 GHz. The

attenuator was evaluated with a 50

Ω source and load

impedance. The following figure shows the circuit

diagram and measured performance.

10,000 pF

10,000 pF

10,000 pF

10,000 pF

10,000 pF

10,000 pF

1 k

1 k

1 k

560

1 k

560

0–20 V

5 V

RF

Output

RF

Input

45

1

2

3

A 4 diode PI attenuator utilizing individual SMP1307-011 PIN diodes is described in the “A Wideband General Purpose PIN Diode Attenuator” Application Note.

-50

-40

-30

-20

-10

0

0

0.5

1.0

1.5

2.0

Frequency (GHz)

SMP1307-027 Attenuation vs. Frequency