## Overview of the PE4224 The **PE4224** is a high-performance **SPDT (Single Pole Double Throw)** RF switch manufactured by Peregrine Semiconductor (now part of pSemi). It is designed based on **UltraCMOS® technology**, which allows it to handle high power and maintain high linearity across a wide frequency range. --- ### Key Technical Specifications | Feature | Specification | | :--- | :--- | | **Frequency Range** | 10 MHz to 3.0 GHz | | **Switch Type** | SPDT (Reflective) | | **Insertion Loss** | ~0.45 dB @ 1.0 GHz | | **Isolation** | 35 dB @ 1.0 GHz | | **P1dB (Input Compression)** | +32 dBm | | **Supply Voltage (Vdd)** | 2.7V to 3.3V | | **Control Interface** | CMOS compatible logic | | **Package** | 6-lead SC-70 | --- ### Core Electronic Characteristics #### 1. UltraCMOS® Technology Unlike traditional GaAs (Gallium Arsenide) switches, the PE4224 uses Silicon-on-Sapphire (SOS) technology. This provides: * **High ESD Tolerance:** It is much more robust against static discharge than GaAs. * **No Blocking Capacitors:** In many designs, DC blocking capacitors are not required if no DC voltage is present on the RF ports. * **Integration:** Logic control and the RF switch are integrated on a single monolithic die. #### 2. Power Handling and Linearity The PE4224 is optimized for low-power and medium-power applications. With a **P1dB of +32 dBm**, it can handle signals up to approximately 1.6 Watts without significant distortion, making it suitable for handheld wireless devices. #### 3. Low Insertion Loss The internal MOSFET structure is designed for minimal resistance when the switch is "ON," ensuring that the signal strength remains nearly intact as it passes through the device (losing only ~0.5 dB). --- ### Pin Configuration and Functionality | Pin # | Name | Description | | :--- | :--- | :--- | | 1 | RF1 | RF Port 1 | | 2 | GND | Ground | | 3 | RF2 | RF Port 2 | | 4 | CTRL | Control Logic Input (High/Low) | | 5 | Vdd | Supply Voltage | | 6 | RFC | RF Common Port | --- ### Control Logic Truth Table The switch state is determined by the voltage applied to the **CTRL** pin: | CTRL Signal | Path Selection | | :--- | :--- | | **Low (0V)** | RFC to RF1 | | **High (Vdd)** | RFC to RF2 | --- ### Typical Applications * **WLAN (802.11 b/g):** Switching between transmit and receive paths. * **Bluetooth:** Signal routing in low-energy devices. * **General Purpose RF Switching:** Used in test equipment or IoT sensors where low power consumption and small form factor are critical.