LM3501 Datasheet, PDF (10/18 Pages) National Semiconductor (TI) – Synchronous Step-up DC/DC Converter for White LED Applications

Typical Performance Characteristics (Continued)
PMOS R_DSON vs. Temperature
Typical V_IN Ripple
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Start-Up (LM3501-16)
3 LEDs, R_LED = 22Ω, V_IN = 3.0V, CNTRL = 2.7V
1) SW, 10 V/div, DC
3) I_L, 100 mA/div, DC
4) V_IN, 100 mV/div, AC
T = 250 ns/div
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SHDN Pin Duty Cycle Control Waveforms
3 LEDs, R_LED = 22Ω, V_IN = 3.0V, CNTRL = 2.7V
1) SHDN, 1 V/div, DC
2) I_L, 100 mA/div, DC
3) I_LED, 20 mA/div, DC
T = 100 µs/div
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LM3501-16, 3 LEDs, R_LED = 22Ω, V_IN = 3.0V, SHDN frequency = 200 Hz
1) SHDN, 1 V/div, DC
2) I_L, 100 mA/div, DC
3) I_LED, 20 mA/div, DC
4) V_OUT, 10 V/div, DC
T = 1 ms/div
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