Technical Manual

760-870 MHz Power Amplifier
Appendix A - 700/800 MHz Circuit Descriptions
A-
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ATLAS 4500 Multimode Station Technical Manual July 2021
A.2.2.6 Receiver DC Supplies
The exciter is supplied nominal 13.8 V through SK1-2. This input supply is then
distributed to IC1 and IC4.
IC1 is configured as a buck DC-DC converter and provides a regulated +5.2 VDC
output.
IC4 is configured as a boost DC-DC converter and provides +25 V DC output.
IC3 regulates +5.2 V supply down to +5 VDC.
IC48 regulates +5 V supply down to +3.3 VDC.
A.3 760-870 MHz Power Amplifier
This section contains information on the following Power Amplifier components:
• Attenuator
• Driver Module
• Output Power Amp
• Power Coupler
• Power Detector
• Harmonic Filter
• PTT Power Control
• Auxiliary Circuits
A.3.1 General Description
The PA contains the following components
• Variable attenuator
• Driver module
• Main power amp
• Cooling system and heat sensor
• Coupler for DPD system.
• Power detector
• Low pass filter
• PTT switch
• Serial flash memory and regulator