HV9925 Supertex, Inc., HV9925 Datasheet
HV9925
Related parts for HV9925
HV9925 Summary of contents
Page 1
... The peak current control scheme provides good regulation of the output current throughout the universal AC line voltage range 264VAC or DC input voltage 400V. The HV9925 is designed with a built in thermal shutdown to prevent excessive power dissipation in the IC. HV9925 ) of approximately 10.5µs. The LED string ...
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... Y = Year Sealed YWW WW = Week Sealed H9925 L = Lot Number “Green” Packaging 8-Lead SOIC (SG) = 50V, unless otherwise noted.) DRAIN Max Units Conditions - V --- - V --- - mV --- 500 μ 8.5V DD(EXT --- - V --- 200 Ω 50mA DRAIN 5 400V DRAIN - mA --- < +85°C. A HV9925 DRAIN DRAIN DRAIN NC ...
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... T = 25°C and V A Min Typ Max - 0.435 0.470 0.525 # 200 300 400 - - - 650 - 8 0.8 - 100 200 300 # - 140 - # - HV9925 = 50V, unless otherwise noted.) DRAIN Units Conditions V --- ns --- ns --- μs --- V --- V --- kΩ 5.0V PWMD °C --- °C --- < +85°C. A ...
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... Junction Temperature, °C Output Capacitance C DRAIN 1000 100 DRAIN Voltage, V Output Characteristics I DRAIN 180 160 125 140 120 100 DRAIN Voltage, V HV9925 J 85 110 vs V DRAIN DRAIN 30 40 ...
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... • ΔI O OFF the forward voltage of the LED string time of the HV9925. The output current in the LED string (I is calculated then as 1/2Δ SENSE O where V is the current sense comparator threshold, and ...
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... The typical DRAIN and R voltage waveforms are shown SENSE in Fig. 3 and Fig. 4. Estimating Power Loss Discharging the parasitic capacitance C output of the HV9925 is responsible for the bulk of the switching power loss. It can be estimated using the following equation: where F is the switching frequency and I S DRAIN current of the HV9925 ...
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... J F Step 3. Calculate total parasitic capacitance using (3 5pF + 5pF +13pF + 8pF = 31pF Step 4. Calculating the leading edge spike duration using (4) and (5): Step 5. Estimating power dissipation in HV9925 at 264VAC using (8) and (10) Switching power loss: 10.5µs P ≈ 130mW SWITCH Minimum duty ratio (0.71 • ...
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... Figure 2. Universal 85-264VAC LED Lamp Driver (I = 20mA 50V) from Example Figure 3. 85-135VAC LED Lamp Driver with PWM Dimming Conduction power loss 170mW COND Total power dissipation in HV9925 78mW + 170mW = 248mW TOTAL Step 6. Selecting input capacitor C Output Power = 30V • 50mA = 1.5W Select C 3.3µF, 250V HV9925 ...
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... Power supply pin for internal control circuits. Bypass this pin with a 0.1uF low impedance capacitor connection DRAIN Drain terminal of the output switching MOSFET and a linear regulator input CH2: V Figure 5. Switch-On Transition – Leading Edge Spike. RSENSE DRAIN Figure 7. PWM Dimming – Falling Edge. CH4: 10×IOUT OUT 9 HV9925 CH1 CH2: V SENSE DRAIN ...
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... This dimension is not specified in the original JEDEC drawing. The value listed is for reference only. Drawings are not to scale. Supertex Doc. #: DSPD-8SOSG, Version C062308 (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to http://www.supertex.com/packaging.html.) Doc.# DSFP-HV9925 A062308 D1 8 Exposed ...