Configurable current sink in tower top amplifier

Abstract

The invention discloses a configurable alarm current sink in a tower top amplifier, which comprises a second-order Bytterworth low-pass filter for converting a PWM signal into an analogue voltage signal and a negative feedback current sink circuit controlled by the analogue voltage signal output by the second-order Bytterworth low-pass filter, wherein the negative feedback current sink circuit is connected with a power supply; and the consumed current of the negative feedback current sink circuit only relates to the magnitude of the analogue voltage signal. The consumed current of the negative feedback current sink circuit has direct proportion relation with the magnitude of the analogue voltage signal. The configurable current sink in the tower top amplifier has the characteristics of configurability, multi-level alarm, low power dissipation of a power supply chip, low heat of the power supply chip, high stability of output voltage of the power supply chip and the like.

Description

[technical field] [0001] The invention relates to radio frequency equipment such as a tower top amplifier TMA, a bidirectional tower top booster (TMB), and in particular to a configurable current pool for tower top radio frequency equipment. [Background technique] [0002] The tower top amplifier or tower top two-way booster is equipped with radio frequency equipment to amplify and receive radio frequency signals. In order to further reduce the attenuation of the received signal in the radio frequency feeder and improve the signal receiving sensitivity, it is installed directly at the bottom of the antenna, away from the base station control unit. [0003] Radio frequency equipment such as tower mounted amplifiers are connected to the base station control unit by radio frequency feeder. While the base station control unit transmits signals through the RF feeder, it also supplies power to the tower-mounted amplifier and other RF equipment through the RF feeder. During the wo...

AI Technical Summary

Problems solved by technology

[0005] The disadvantage of this design is obvious

First of all, under the premise of a certain power supply voltage, the current consumed by the current pool is determined by the resistance, so the amount of current that the current pool can draw is fixed and cannot be configured. Tower-mounted amplifiers configured for different requirements need Design the corresponding current pool, so the use of the existing current pool is relatively limited; secondly, due to the wide range of supply voltage, Ys in the above formula needs to be the output voltage of the power chip, which leads to the current consumption of the current pool All of them are added to the power chip, resulting in aggravated heating of the power chip, and a more serious problem is that it will affect the stability of the output voltage of the power chip, thereby affecting the power supply to the LNA, which may affect the performance of the tower top amplifier.

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