CN201690205U

CN201690205U - Zero-crossing detection circuit

Info

Publication number: CN201690205U
Application number: CN2010201940079U
Authority: CN
Inventors: 侯炳彬
Original assignee: Wuxi Hodgen Technology Co Ltd
Current assignee: Wuxi Hodgen Technology Co Ltd
Priority date: 2010-05-18
Filing date: 2010-05-18
Publication date: 2010-12-29
Anticipated expiration: 2020-05-18

Abstract

The utility model discloses a zero-crossing detection circuit, which comprises 220V mains supply (1), a transformer (2), a zero-crossing detection loop (3), a singlechip (4), a relay (5) and peripheral circuit (6). The 220V mains supply (1) is connected with the primary of the transformer (2) and then outputted through the secondary of the transformer (2). When waveform is transformed from positive semi-cycle to negative semi-cycle, the zero-crossing detection loop (3) detects zero-crossing signals and then switching frequency signals are sent to the singlechip (4) and processed by singlechip (4), finally control signals are outputted, then the relay (5) is actuated, and the periphery circuit starts to operate. Due to the adoption of the zero-crossing detection circuit, the initial voltage of the peripheral circuit when in low voltage also can start to work, thereby preventing the peripheral circuit from being damaged due to too high initial voltage.

Description

Zero cross detection circuit

Technical field

The utility model relates to a kind of zero cross detection circuit, particularly a kind of zero cross detection circuit that comes the daily electrical equipment of power on/off by the adhesive of Single-chip Controlling relay.

Background technology

When daily electrical equipment is in the past worked in the 220V mains-supplied, the single-chip microcomputer output signal, the relay adhesive, the corresponding civil power AC signal angle of flow is at random.

When adopt adopting aforesaid way that daily electrical equipment is powered,, may damage the device in the peripheral circuit because of starting voltage is excessive if when this moment, AC signal was maximum.

The utility model content

The utility model is intended to overcome the described daily electrical equipment of background technology, when AC signal is maximum, may damage the shortcoming of the device in the peripheral circuit because of starting voltage is excessive.

In order to overcome the problems referred to above, the utility model has designed a kind of zero cross detection circuit, comprises the 220V civil power, transformer, zero passage detection loop, single-chip microcomputer, relay and peripheral circuit.During work, the 220V civil power is received the elementary of transformer, through the secondary output of transformer, change to negative half period from positive half cycle when waveform, after the zero passage detection loop detects zero cross signal, the switching frequency signal is sent into single-chip microcomputer, after single-chip microcomputer was handled, the output control signal was by the adhesive of control relay, control peripheral circuit, so just can guarantee that peripheral circuit just starts working when low-voltage.

By above-mentioned improvement, its beneficial effect is: after adopting zero cross detection circuit, just can guarantee that the starting voltage of peripheral circuit is started working when low-voltage, avoid damaging because of starting voltage is excessive peripheral circuit.

Description of drawings

Fig. 1 is the structure diagram that is used for the zero cross detection circuit of one control air valve switching in the gas heater.

Wherein the symbol description of Fig. 1 is as follows: 1---220V civil power 2---transformer 3---zero passage detection loop 4---single-chip microcomputer 5---relay 6---peripheral circuit.

Embodiment

As shown in Figure 1, be to be used for the zero cross detection circuit that one control air valve opens and closes in a kind of gas heater, comprise 220V civil power 1, transformer 2, zero passage detection loop 3, single-chip microcomputer 4, relay 5 and peripheral circuit 6.During work, 220V civil power 1 is received the elementary of transformer 2, through the secondary output of transformer 2, change to negative half period from positive half cycle when waveform, after zero passage detection loop 3 detects zero cross signal, the switching frequency signal is sent into single-chip microcomputer 4, after single-chip microcomputer 4 was handled, the output control signal was by the adhesive of control relay 5, control peripheral circuit 6 work, so just can guarantee that peripheral circuit just starts working when low-voltage.

Claims

1. zero cross detection circuit, it is characterized in that comprising 220V civil power (1), transformer (2), zero passage detection loop (3), single-chip microcomputer (4), relay (5) and peripheral circuit (6), 220V civil power (1) is received the elementary of transformer (2), through the secondary output of transformer (2), after waveform is changed to negative half period from positive half cycle, and zero passage detection loop (3) detect zero cross signal, the switching frequency signal is sent into single-chip microcomputer (4), single-chip microcomputer (4) is handled back output control signal, relay (5) adhesive, peripheral circuit (6) work.