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20-Lead 4x4 mm QFN

The SP4257 is a high-isolation CMOS Switch designed

for wireless applications, covering a broad frequency range

from near DC up to 3000 MHz. This single-supply SPDT

switch integrates a two-pin CMOS control interface. It also

provides low insertion loss with extremely low bias

requirements while operating on a single 3-volt supply. In a

typical wireless application, the SP4257 provides

unprecedented isolation and integration.

The SP4257 is manufactured on SIPAT’s CMOS

process, a patented variation of silicon-on-insulator (SOI)

technology on a sapphire substrate, offering the performance

of GaAs with the economy and integration of conventional

CMOS.

Product Specification

50

Ω SPDT Absorptive CMOS

DC – 3.0 GHz RF Switch

Product Description

Figure 1. Functional Diagram

SP4257

Features

at 1000 MHz and 0.95 dB at 2000 MHz

Parameter

Condition

Minimum

Typical

Maximum

Units

DC

3000

MHz

Insertion Loss

1000 MHz

2000 MHz

3000 MHz

0.75

0.95

1.2

0.95

1.15

1.4

dB

Isolation Input to Output

1000 MHz

2000 MHz

3000 MHz

61

46

40

64

50

44

dB

Isolation Output to Output

1000 MHz

2000 MHz

3000 MHz

57

54

42

63

60

48

dB

Input IP2

5 MHz - 1000 MHz

80

dBm

Input IP3

5 MHz - 1000 MHz

50

55

dBm

1000 MHz

29

31

dBm

Switching Time

50% CTRL to 10 / 90 RF

2

µs

5 MHz - 1000 MHz

15

Notes: 1. Device linearity will begin to degrade below 5 MHz.

2. Note Absolute Maximum ratings in Table 3.

3. Measured with a 1 ns risetime, 0/3 V pulse and 500 MHz bandwidth

Figure 2. Package Type

RF1

RF2

50

Ω

50

Ω

CMOS

Control

Driver

ESD

ESD

50

Ω

RFC

CTRL CTRL2

Tel: +86-23-62808818

Fax: +86-23-62805284

www.sipatsaw.com / sawmkt@sipat.com