PROTECTION BOARD FOR LDMOS MOSFET AMPLIFIER WITH DUAL TANDEM MATCH ALL-IN-ONE

Description

Features:
• Overload protection
• Current limitation
• Short circuit protection
• Over voltage protection
• Diagnostic feedback with load current sense
• Operating voltage 24 – 58 VDC
• Operating current 44 A max
• On-state resistance 7.2 mΩ
TANDEM MATCH FREQ. 1.5-54MHz
Reset button to recover from protection.
To allow the switch to be disabled by an emergency signal, there are 4 protection triggers placed on board:
• high VSWR protector to disconnect the amplifier from power supply if SWR rises higher than preset
level 2.0:1 (may be varied by user) . Forward and reflected wave voltages from dual internal directional
coupler determine the VSWR independent of power level.
LPF error high SWR (may be varied by user).
• output power excess protector to disconnect the amplifier if output power is more than preset level. Fine
threshold tuning from 150W up to 1500W.
• DC current excess protector to disconnect the amplifier if current consumption is more than preset level.
Fine threshold tuning from 15 up to 40A.
Red LED shows which trigger is on. Power off and then on to reset device.
BT50085B has a min switch-off time as low as 30 microseconds, so fast enough to protect the amplifier in case of emergency.
The on board current sensor provides +VDC for external current meter. Meter impedance must be at least 10 KOhm.
(Divide the current through the BTS switch by 13000, then multiply by 3300 so you get the supply voltage by "ID".
This information is in the datasheet on BTS50085-1TMB)
THANK YOU
SV2RIF
SV2RKF