Receivers rely on low-noise amplifiers (LNAs) to pull in low-level signals, but those LNAs can be damaged by high-level signals. For protection, Skyworks Solutions has developed a compact passive PIN diode limiter. The model SKY16602-632LF is ideal for protecting LNAs in cellular communications and other commercial and military wireless receiver systems (including S-band radar) from 0.2 to 4.0 GHz.
This is a fully integrated module, featuring a PIN limiter diode, a Schottky diode, and two DC blocking capacitors, all packed into a two-pin 2.3 × 2.3 mm MLP lead-free package. It does not require a bias voltage, and is designed to pass desired signals with low loss while blocking potentially damaging high-level signals.
The model SKY16602-632LF limiter (see photo) provides the protection with a minimum of insertion loss and with nanosecond recovery time. It features a low limiting threshold level of typically +5 dBm, and handles maximum continuous-wave (CW) input power to 12 W and maximum pulsed (based on 1-μs pulses) input power to 120 W. Insertion loss is typically 0.3 dB at 900 MHz, with maximum insertion loss of 0.5 dB measured at that frequency (and 0-dBm input test power).
Return loss is typically 14 dB at the same test frequency. The recovery time at 900 MHz is a mere 5 ns. For an input level of +10 dBm at 900 MHz, the limiter exhibits flat leakage power of +6 dBm. The limiter has junction-to-case thermal resistance of typically 114°C/W. It is designed for use at operating temperatures from -40 to +85°C.
Since electrostatic discharge (ESD) can damage even protection devices such as this, the compact PIN diode limiter has been fully characterized for reliable use when faced with unexpected ESD incidents. It is rated for ESD of 1000 V per the charged-device model (CDM), 250 V per the human-body model (HBM), and 150 V per the machine model (MM).
Skyworks Solutions, Inc., 20 Sylvan Rd., Woburn, MA 01801; (781) 376-3000, FAX: (781) 376-3100