原标题：Microchip HV96001离线LED驱动器解决方案

　　microchip公司的HV96001是离线LED驱动器解决方案,可以进行线性调光和PWM调光,PWM调光具有无闪烁调光,低至0.01%或更低.器件可调整AC/DC转换器输出电压,以维持大范围LED负载电压时的高转换效率.它还能对LED电流幅度进行精密控制,从而维持恒定的色温.HV96001包括两个反馈稳压器,它用来控制反馈输出电压的控制,而升压稳压器用来控制LED电流的幅度.光偶驱动器电路驱动光偶合器,依次提供控制信号,用来驱动反馈转换器的控制输入.HV96001输入电压从8V到60V,PWM调光宽度低于150ns,调光频率高达20kHz.16L VQFN 3 mm x 3 mm和16L SOIC窄体封装,主要用在离线LED照明应用.本文介绍了HV96001主要特性,框图,典型应用电路图以及离线LED驱动器评估板ADM01030主要特性,电路图,材料清单和PCB设计图.

　　The HV96001 LED driver targets offline lighting applications requiring wide dimming capability. The device is capable of linear dimming and PWM dimming, with the PWM dimming capable of flicker-free dimming down to 0.01% level and lower.

　　The HV96001 is specifically adapted to LED driver designs that accommodate a wide range of the LED load voltage. The device adjusts the output voltage of the AC to DC conversion stage for maintaining a high conversion efficiency over a wide range of the LED load voltage. It also maintains a precise control over the LED current amplitude, thereby maintaining the consistent color temperature.

　　The adaptability of the device to wide range PWM dimming allows for a stable control of the LED current waveform for PWM dimming pulse widths down to 150 ns and lower.The HV96001 driver IC adjusts the flyback converter output voltage such that the boost converter (BC) operates with a small difference between the boost converter input and output voltage, also referred to as the headroom voltage. Operating the boost converter with a small headroom voltage, or, more or less equivalent, operating with a small voltage step-up ratio allows the boost converter to be physically small and operate at a higher efficiency.

　　The HV96001 includes two feedback regulators, the flyback regulator for control of the flyback output voltage and the boost regulator for control of the LED current amplitude. An optocoupler driver circuit drives the optocoupler, which in turn provides a control signal for driving the control input of the flyback converter.

　　HV96001主要特性:

　　• Wide Input Voltage Range: 8V to 60V

　　• Linear (analog) Dimming:

　　- With wide range of amplitude control of the LED current

　　• Pulse-Width Modulation (PWM) (digital) Dimming:

　　- Dims down to 0.01% and lower

　　- With PWM pulse width lower than 150 ns

　　- PWM dimming frequency up to 20 kHz

　　• Flyback Converter:

　　- With automatic output voltage adjustment for maintaining high system efficiency

　　• Boost Converter:

　　- With near zero output voltage ripple for a ripple-free LED current

　　- 100 Hz/120 Hz ripple rejection

　　- 200 kHz fixed switching frequency

　　- SEPIC topology compatible

　　• VDD Regulator:

　　- 60V input voltage/5V output voltage

　　- 10 mA drive for supplying external loads

　　• Fault Recovery with Auto-Retry Delay Set Using Timing Capacitor

　　• Undervoltage Detection of:

　　- VDD voltage

　　- Supply voltage (Flyback output voltage)

　　• Overvoltage Detection of:

　　- LED load voltage (Boost output voltage)

　　• Overcurrent Detection of:

　　- Load switch current

　　• Stuck-at-Zero Detection of:

　　- DIM input signal

　　• Short Circuit Protection of Output with Auto-Retry Delay

　　HV96001应用:

　　• Offline LED lighting applications featuring wide range for PWM dimming and linear dimming.

　　PACKAGES

　　• 16L VQFN, 3 mm x 3 mm

　　• 16L SOIC, Narrow Body

　　图1.HV96001框图

　　图2.HV96001典型应用电路图

　　HV96001离线LED驱动器评估板ADM01030

　　The HV96001 Offline LED Driver Evaluation Board Kit includes:

　　• HV96001 Offline LED Driver Evaluation Board (ADM01030)

　　• Important Information Sheet

　　HV96001 Offline LED Driver Evaluation Board is fully assembled and tested to evaluate and demonstrate the HV96001 LED driver. In the primary side, the flyback converter has implemented an active Power Factor Correction (PFC) control algorithm by a PIC controller that commands the switching sequence in such a manner that the input current follows the input voltage envelope. Therefore, the power factor of the application is PF > 0.9, for the entire input voltage range. The power factor value (PF) should be tuned by using R52 potentiometer according to the rated power of the LED load used. The tuning should be done in no dimming conditions. For example, to obtain a power factor PF over 0.9 for a 42W LED load, the value for the R52 resistor will be set to 750Ω. Check if mechanical jumper JP1 (provided) is mounted on the J11 connector.

　　The output voltage and current delivered by the HV96001 Offline LED Driver Evaluation Board can be set by using the rotary encoder E1. After the board is supplied with 230VAC the initial PWM dimming value is 50% and current reference limit LCR is 200 mV. To increase the PWM duty cycle the encoder must be rotated to the right (clockwise) and to decrease the encoder must be rotated to the left (counter-clockwise). The actual value of the PWM percent reference will be displayed on the LCD from the secondary side of the flyback, in the first information row, as in the picture below. The value of 0.15% is given by the minimum voltage over the UVLO protection performed by the HV96001 for the input voltage. When the PWM is getting lower than 15%, the LCR is decreasing linearly to avoid big currents spikes.

　　For the current increase or decrease, the encoder must be pressed to activate the switch button and to be rotated to the left or to the right in a similar way as for PWM dimming variation described above.

　　The maximum value of the PWM dimming is 100% and of the current reference (LCR)is 400 mV. The maximum LCR value of 400 mV is corresponding to a 0.7-0.8A current through the LED Load.

　　图3.离线LED驱动器评估板ADM01030外形图

　　离线LED驱动器评估板ADM01030材料清单:

　　材料清单(机械部件):

　　材料清单(不常用部分):