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IR2167 is integrates completely, protects completely, may actuate all type fluorescent lamp’s 600V electron ballast control chip. The PFC electric circuit (CCM) works by the critical breakover pattern, may obtain the very high power factor, and has the low harmonic constant 煟 abundant decayed tooth mold 犌 to damp stretches jian Miao Gu silly ao # Sang Yaobo to guarantee bites returns to the sodium light liquor characteristic including the preheat interval and the frequency adjustable, the ignition frequency adjustable, the movement frequency adjustable, the dead time adjustable, the overflow threshold voltage adjustable. These have provided enormous convenient for the engineering design personnel. In addition, IR2167 also has the consummation protection function: Like the filament failure protection, the tube triggering defeat protects, the lamp life protection, the direct-current bus bar undervoltage replacement and restarts automatically moves and so on functions. This chip uses 20 pin DIP or the SOIC seal.

1 pin arrangement and function

IR2167 pin arrangement chart as shown in Figure 1, various pins’ function like table 1 arranges in order.

2 based on IR2167 PFC control circuit

IR2167 PFC and the ballast control chip has the undervoltage blockade, preheating, the ignition, the movement as well as the breakdown response and so on key job pattern. Shown in Figure 2 is the IR2167 work flow chart.

The majority electronic ballasts hoped that the electric circuit speaking of exchanges the electrical network for the pure resistance, but electric circuit whether mainly to be decided for the pure resistance in the electric circuit between the input voltage and the input current phase as well as the input current profile shape to be whether consistent with input voltage’s sine wave configuration. Between its input current and input voltage’s phase angle cosine usually defines as the power factor (PF), but the input current profile and the input voltage profile’s uniformity defines as the total harmonic distortion (THD). The power factor is 1 (biggest) expressed that the angle of phase shift is zero, THD is 0% expression pure wave (does not have distortion). In order to serve this purpose, IR2167 contains a power factor compensating circuit, it may aim at the exchange input voltage to produce exchange input current. IR2167 control method based on its work in critical breakover pattern (CCM) pressure-rise converter. Namely in the PFC MOSFET each switching period, the electric circuit has waited for discharges the zero hour to the inductance electric current, only then once more clears PFC MOSFET. In fact, the PFC MOSFET turn-on frequency (>10kHz) is bigger than the mains frequency far (50~60Hz). Figure 3 is based on a IR2167 simple PFC control circuit.

    Because inductance LPFC receives the rectified output the end and - the end, therefore, in the MPFC clear time, in the LPFC electric current linearity increases. But when MPFC shutdown, LPFC connection in rectified output end and direct-current bus bar electric capacity CBUS (through diode DPFC) both sides, thus in this time LPFC the electric current flows to CBUS. Because MPFC uses the high frequency work, the CBUS voltage will imitate to a specific value. But the IR2167 feedback loop through continuously examines the direct-current bus bar voltage and adjusts MPFC the turn-on time to come correspondingly the voltage regulation to a fixture. Because the negative feedback return route is the low speed and the low gain, therefore, the inductance mean current may follow the low frequency network voltage smoothly, thus realizes the high power factor and low THD.

This PFC control circuit needs to use IRF2167 chip VBUS, COMP, ZX and the PFC four pins. And the VBUS foot uses in examining the DC voltage (through non-essential resistance voltage divider), the COMP foot uses for to establish MPFC the turn-on time and the feedback loop speed, the ZX foot examination inductance electric current zero crossing (through PFC inductance two side winding), the PFC foot is the MPFC electronics grid actuates the output pin.

    The MPFC turn-off time is decided in LPFC discharges zero the time. Available connects ZX foot’s LPFC two side winding to examine zero electric current. If the electric current has not reduced to zero, then the ZX foot will not examine the rise along, this time MPFC will maintain the shutdown. If the ZX foot has not examined the rise along the time surpasses 500ms, then the chip interior timer will force the MPFC clear (turn-on time by COMP foot’s voltage decision). Presents the correct rise and the drop until the ZX foot along the signal, up to PFC normal work.

Table 1 IR2167 pin arrangement