0.1 to 3.8 GHz SP4T Antenna Switch

The SKYA21029 is a single-pole, four-throw (SP4T) antenna switch with an internal 50 Ω termination. The high-linearity performance and low insertion loss achieved by the SKYA21029 make it an ideal choice for embedded cellular telematics modules and OBD-II cellular modems.

The symmetric port designs provide flexibility in signal routing for both receive diversity and higher power TD-SCDMA/TDD-LTE, WCDMA/FDD, and LTE transmit/receive applications.

Switching is controlled by three CMOS/TTL-compatible control voltage inputs (V1, V2, and V3). Depending on the logic voltage level applied to the control pins, the ANT pin is connected to one of four switched RF outputs (RF1 to RF4) using a low insertion loss path, while the paths between the ANT pin and the other RF pins are in a high isolation state.

The antenna path can also be closed on a 50 Ω load when it needs to be terminated. The 50 Ω load is internally grounded. No external blocking capacitors are required on the RF paths unless VDC is externally applied.

The SKYA21029 is manufactured in a compact, 14-pin 2.0 x 2.0 mm, Quad Flat No-Lead (QFN) package.


Product LifecycleIn Production
Description (Absorptive/ Reflective)SP4T (R)
Frequency (GHz) Min.0.1
Frequency (GHz) Max.3.8
Typ. Isol. (dB)42-26
Typ. IL (dB)0.40-0.60
Typ. IIP3 (dBm)70
Typ. IP1 dB (dBm)39
PackageQFN, 14L
Package (mm)2 x 2 x 0.55


  • Broadband frequency range: 0.1 to 3.8 GHz
  • Low insertion loss: 0.45 dB typical @ 2.7 GHz
  • High isolation: >31 dB @ 2.7 GHz
  • Internal 50 Ω port to control diversity antenna impedance when device is not in use
  • Integrated logic
  • Automotive Level-3 PPAP available upon request
  • IMDS material declaration available at production release
  • Extended production life to support automotive requirements
  • Independent BOM management to minimize PCN risk
  • Small QFN (14-pin, 2.0 x 2.0 mm) package
  • (MSL1, 260 °C per JEDEC J-STD-020)

Product Documents



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Cellular Telematics

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Remote Keyless Entry

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