A6211 ALLEGRO [Allegro MicroSystems], A6211 Datasheet - Page 12

• Manufacturer Part Number: A6211
• Description: Constant-Current 3-Ampere PWM Dimmable Buck Regulator LED Driver
• Manufacturer: ALLEGRO [Allegro MicroSystems]

A6211
Figure 13. Waveforms showing the effects of adding a small filter capacitor across the LED string
• Operating conditions: at 200 Hz, V
• CH1 (Red) = V
CH3 (Green) = i
IN
LED
(10 V/div), CH2 (Blue) = V
(500 mA/div), CH4 (Yellow) = Enable (5 V/div), time scale = 1 ms/div
IN
C1,C2
C1,C2
= 24 V, V
C3
C4
C3
C4
V
V
OUT
i
V
i
V
V
V
LED
LED
OUT
OUT
EN
EN
IN
IN
OUT
(10 V/div),
Panel 13A. Operation without using any output
capacitor across the LED string
Panel 13B. Operation with a 0.68 μF ceramic
capacitor connected across the LED string
Constant-Current 3-Ampere PWM Dimmable
= 15 V, f
SW
= 500 kHz, L = 10 μH, duty cycle = 50%
t
t
Buck Regulator LED Driver
115 Northeast Cutoff
1.508.853.5000; www.allegromicro.com
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 U.S.A.
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