CAT4201_15 Datasheet, PDF (6/12 Pages) ON Semiconductor – High Efficiency Step Down LED Driver

CAT4201
TYPICAL OPERATION CHARACTERISTICS
(V_IN = 13 V, I_LED = 300 mA, L = 22 mH, C₁ = 4.7 mF, C₂ = 10 mF, T_AMB = 25°C unless otherwise specified)
Figure 20. RSET Transient Response
Figure 21. Line Transient Response
(10 V to 13 V)
External Component Selection
Table 4 provides the recommended external components L and C2 that offer the best performance relative to the LED current
accuracy, LED ripple current, switching frequency and component size.
Table 4. EXTERNAL COMPONENT SELECTION
1 LED
2 LEDs
LED Current (mA)
L Inductor (mH)
C2 Capacitor (mF)
L Inductor (mH)
C2 Capacitor (mF)
≥150
22
4.7
22
4.7
< 150
33
4.7
47
2.2
47
10
NOTE: Larger C2 capacitor values allow to reduce further the LED ripple current if needed.
Table 5. INDUCTOR SELECTION DEPENDING ON VBAT SUPPLY VOLTAGE
VBAT Supply Voltage (V)
Minimum Inductor L (mH)
< 26
22
≥ 26
33
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