RF power transistor for 945 MHz infrastructure
The STMicroelectronics PD57018-E is an LDMOS RF power transistor designed for the 945 MHz band, delivering 18 W output power with 16.5 dB gain when tested at 28 V and 100 mA bias. The 65 V drain rating provides headroom for load mismatch and peak envelope power.
The PowerSO-10 exposed bottom pad is the primary heat path. The PCB footprint should include a copper pad matching the exposed area, connected through thermal vias to an inner-plane or backside copper pour. Without adequate thermal management, the 2.5 A drain current at 28 V can push the die beyond its safe operating area during sustained transmit.