RD04HMS2 single-stage amplifier with f=135-175MHz evaluation board
This application note presents the RDO4HMS2 single‑stage amplifier evaluation board, covering its circuit topology, PCB layout, component list, thermal design, and measured RF performance. It includes typical specifications such as a 135‑175 MHz frequency range, 0.2 W input power and 5.5 W output power.
The document provides detailed graphs of frequency versus output power, gain, drain efficiency and quiescent current, as well as thermal calculations for the heat‑sink design. All data are based on measurements taken at VDS = 12.5 V and VDS = 9.1 V.
| Frequency range | 135‑175 MHz |
|---|---|
| Typical input power | 0.2 W |
| Typical output power | 5.5 W |
| Quiescent current | 100 mA |
| Operating current | 0.65 A |
| Board dimensions | 80 mm × 55 mm |
| Board material | FR‑4 |
| Recommended heat‑sink thermal resistance | < 9.3 °C/W |
The board operates from 135 MHz to 175 MHz.
Typical output power is 5.5 W.
The board measures 80 mm by 55 mm.
The quiescent current is 100 mA.