Alternating current signal output module

Abstract

The utility model aims to provide the frequency-adjustable AC signal output module with the load, so that the verification efficiency of the wireless charging function of the existing electronic product can be improved. The device comprises a signal generation module, a filtering module and a signal processing module which are connected in sequence, the signal processing module comprises two output channels, the two output channels comprise a feedback amplifier and a high-speed buffer which are connected in sequence, and the signal generation module comprises a DDS signal generator. And two groups of output ends of the DDS signal generator are respectively connected to the two paths of output channels through the filtering module. The signal output module is applied to the technical field of signal output modules.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of signal output module, especially involves an alternating current signal output module. BACKGROUND

[0002] The wireless charging technology can solve the problem that the existing electronic product needs to be connected with a charging line and the operation is complicated, and the implementation of charging needs to include the cooperation of a charging end and a receiving end, wherein the charging end generates an alternating current signal. The wireless charging circuit on the market currently needs to invert the direct current signal to an alternating current signal, and the alternating current signal needs to have a certain load carrying capacity. The existing scheme generally uses a function generator combined with a peripheral circuit, or a power amplifier device. It is difficult to cover the charging needs of various frequency intervals, and different models of products cannot be simultaneously compatible for wireless charging test during detection.

[0003] If a frequency adjustable and load carrying alternating current signal output module can be provided, the efficiency of the existing electronic product wireless charging function verification can be improved. UTILITY MODEL CONTENTS

[0004] The utility model solves the technical problem of overcoming the deficiency of the prior art, and provides a frequency adjustable and load carrying alternating current signal output module, which can improve the efficiency of the existing electronic product wireless charging function verification.

[0005] The utility model adopts the technical scheme: the utility model discloses a signal generation module, filter module and signal processing module connected in turn, the signal processing module includes two output channels, and two output channels include feedback amplifier and high-speed buffer connected in turn, the signal generation module includes DDS signal generator, and two groups of output ends of DDS signal generator are connected to two output channels through filter module respectively.

[0006] From the above scheme, it can be seen that the signal generation module is used in cooperation with the external MCU to generate two-phase adjustable, frequency adjustable and load carrying two-way arbitrary waveform signals, which can realize the test purpose of the small power wireless charging circuit conveniently and quickly. The signal generation module realizes the generation of double signals, and the phase difference is set to 180° to simulate the alternating current signal during wireless charging. Different output frequencies are set to realize different wireless charging signal frequencies. The filter module realizes first-order low-pass filtering. The feedback amplifier and the high-speed buffer are used in cooperation to realize composite operational amplifier, which can realize very small input bias current and very large input resistance, thereby reducing the error, and the high-speed buffer realizes current output to achieve the load carrying capacity.

[0007] A preferred solution is that the DDS signal generator is a signal generator of model AD9834.

[0008] A preferred solution is that the filter module comprises an RC circuit composed of a first resistor and a first capacitor.

[0009] A preferred solution is that the positive input end of the feedback amplifier is connected with the output end of the signal generation module, the input end of the high-speed buffer is connected with the output end of the feedback amplifier, the output end of the high-speed buffer is connected with a second resistor, and the negative input end of the feedback amplifier is connected with both ends of the second resistor through a second capacitor and a third resistor respectively.

[0010] A preferred solution is that the feedback amplifier is an amplifier chip of model AD8065, and the high-speed buffer is a buffer chip of model BUF634. BRIEF DESCRIPTION OF DRAWINGS

[0011] Fig. 1 is a system block diagram of the utility model;

[0012] Fig. 2 is a circuit principle diagram of the signal generation module;

[0013] Fig. 3 is a circuit principle diagram of the signal processing module. DETAILED DESCRIPTION

[0014] As shown in the figure, Figs. 1-3 in the embodiment, the utility model includes signal generation module 1, filter module 2 and signal processing module 3 connected in turn, the signal processing module 3 includes two-way output channel, two-way the output channel includes feedback amplifier and high-speed buffer connected in turn, the signal generation module 1 includes DDS signal generator U600, and two groups of output ends of the DDS signal generator U600 are connected to two-way the output channel through the filter module 2 respectively. Fig. 2 As shown in the figure, the DDS signal generator U600 is a signal generator of model AD9834, is used as signal source, can realize the generation of two-way signal of 0.004Hz ~ 35MHz, and the signal of the two-way is set to the signal of phase difference 180 °, namely can simulate the alternating current signal when wireless charging, realizes the signal frequency of different wireless charging by setting different output frequency, through the cooperation of external MCU and DAC unit, the voltage value adjustment of the 1 pin of the DDS signal generator U600 is carried out, to reach the purpose of adjusting output amplitude.

[0015] In the embodiment, the filter module 2 comprises an RC circuit composed of a first resistor and a first capacitor, the filter module 2 forms a first-order low-pass filter through the RC circuit, and by setting a cut-off frequency to about 32 MHz, the AC signal of 13.56 MHz is compatible.

[0016] In the embodiment, the positive input end of the feedback amplifier is connected with the output end of the signal generation module 1, the input end of the high-speed buffer is connected with the output end of the feedback amplifier, the output end of the high-speed buffer is connected with a second resistor, and the negative input end of the feedback amplifier is connected to both ends of the second resistor through a second capacitor and a third resistor, respectively. The feedback amplifier is an AD8065 amplifier chip, and the high-speed buffer is a BUF634 buffer chip. The feedback amplifier is combined with the high-speed buffer as a composite operational amplifier, thereby realizing a JFET stage input operational amplifier, achieving a very small input bias current and a very large input resistance, thereby reducing errors; through the output current providing capability of the high-speed buffer, the BUF634 buffer chip has a current output capability of 250 mA, and the test of a small-power wireless charging circuit can be realized.

[0017] The existing AC signal output module needs a function generator combined with a power amplifier or other power amplification peripheral circuit to be realized, and the purpose of the utility model is to test a small-power wireless charging circuit, such as a wireless charging circuit of a handwriting pen and the like. The volume of the product to be tested is relatively small, the volume of the existing output module is too large, and the cost is high, and the utility model can well balance the volume and precision of the test equipment.

[0018] Although the embodiments of the utility model are described in actual schemes, but do not constitute the limitation to the meaning of the utility model, for the person skilled in the art, according to the modification of the embodiments and the combination with other schemes in the specification, it is obvious.

Claims

1. An alternating current signal output module, characterized by: It includes the signal generation module (1), the filter module (2) and the signal processing module (3) connected in turn, the signal processing module (3) includes two output channels, two said output channels include feedback amplifier and high-speed buffer connected in turn, the signal generation module (1) includes DDS signal generator U600, two groups of output terminals of the DDS signal generator U600 are connected to two said output channels through the filter module (2) respectively.

2. The AC signal output module of claim 1, wherein: The DDS signal generator U600 is a signal generator with model AD9834.

3. The AC signal output module of claim 1, wherein: The filter module (2) includes RC circuit composed of first resistance and first capacitance.

4. The AC signal output module of claim 1, wherein: The positive input end of the feedback amplifier is connected with the output end of the signal generation module (1), the input end of the high-speed buffer is connected with the output end of the feedback amplifier, the output end of the high-speed buffer is connected with the second resistance, the negative input end of the feedback amplifier is connected to the two ends of the second resistance through the second capacitance and the third resistance respectively.

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