HV9982DB1 Supertex, HV9982DB1 Datasheet - Page 5

• Manufacturer Part Number: HV9982DB1
• Manufacturer: Supertex

Specifications of HV9982DB1

• Lead Free Status / Rohs Status: Supplier Unconfirmed

Output Voltage refers to VO+ voltage measured w.r.t GND). The hysteretic over voltage protection is shown in Fig. 4 where
the output voltage is consistently maintained between 82V and 92V.
Fig. 4: Open LED Operation
The recovery from an open LED condition is shown in Fig. 5. Two spikes are observed in the LED current. These spikes
are caused by the output capacitor discharging into the LEDs since the capacitor voltage is higher the LED string voltage.
This causes the HV9982 to go into a hiccup mode short circuit condition till the capacitor voltage becomes lower than the
LED string voltage (as seen by the dip the output voltage). Once all fault conditions are cleared, the LED current starts up
smoothly into normal operation. Fig. 6 shows the recovery with a smaller timescale.
Fig. 5: Recovery from Open LED Operation
Fig. 6: Recovery (smaller timescale)
C1 (Yellow): Output Voltage of Channel 1(20V/div)
C4 (Green): Output Current for Channel 1 (50mA/div)
Time Scale: 20ms/div
C4 (Green): Output Current for Channel 1 (50mA/div)
Time Scale: 20mA/div
C1 (Yellow): Output Voltage of Channel 1(20V/div)
C1 (Yellow): Output Voltage of Channel 1(20V/div)
C4 (Green): Output Current for Channel 1 (50mA/div)
Time Scale: 500μs/div
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HV9982DB1