A6211 ALLEGRO [Allegro MicroSystems], A6211 Datasheet - Page 7

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

A6211
Figure 3. Efficiency versus LED Current at various LED voltages
Operating conditions: f
95
90
85
80
75
70
0
0.5
V
V
SW
V
IN
IN
IN
= 12 V, V
= 12 V, V
= 1 MHz
= 24 V, V
1.0
0.001
LED Current, i
0.01
0.1
Figure 5. Average LED Current versus PWM dimming percentage
Operating conditions: V
1
OUT
OUT
OUT
0.1
= 5.5 V
= 3.5 V
= 15 V
1.5
LED
(A)
2.0
Constant-Current 3-Ampere PWM Dimmable
IN
i
LED
2.5
= 12 V, V
= 3 A
1
Duty Cycle (%)
3.0
OUT
i
LED
= 3.5 V, f
= 1.4 A
Figure 4. Efficiency versus LED Current at various switching frequencies
Operating conditions: V
i
LED
SW
= 2 A
95
90
85
80
75
70
= 1 MHz, f
0
10
Buck Regulator LED Driver
f
SW
PWM
= 500 kHz
0.5
= 200 Hz, L = 10 μH
IN
= 12 V, V
1.0
LED Current, i
115 Northeast Cutoff
1.508.853.5000; www.allegromicro.com
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 U.S.A.
OUT
100
1.5
= 5.5 V
f
SW
LED
= 2 MHz
(A)
2.0
f
SW
= 1 MHz
2.5
3.0
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