A8514KLPTR-T Allegro Microsystems Inc, A8514KLPTR-T Datasheet - Page 29

• Manufacturer Part Number: A8514KLPTR-T
• Description: IC LED DVR WHT 4X80MA 16-ETSSOP
• Manufacturer: Allegro Microsystems Inc

Specifications of A8514KLPTR-T

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

A8514
Step 9
the input disconnect 1X current limit to 3 A by choosing a sense
resistor. The calculated maximum value of the sense resistor is:
The R
SC
Choosing the input disconnect switch components. Set
chosen is 0.033 Ω, a standard.
R
SC
4.7 μF
C
(max) = V
100 kΩ
IN
10 to 14 V
V
IN
= 0.104 (V) / 3.0 (A) = 0.035 Ω
V
Figure 34. The schematic diagram showing calculated values from the design example above.
C
SENSEtrip
0.033 Ω
249 Ω
R
R
ADJ
SC
11 kΩ
R
ISET
/ 3.0 (A)
20 Ω
R
C
0.1 μF
C
VDD
22 nF
C
C
R
10 kΩ
FSET
Q1
Wide Input Voltage Range, High Efficiency
GATE
VSENSE
VIN
VDD
FAULT
PWM/EN
APWM
ISET
FSET/SYNC
10 μH
L1
AGND
(28)
A8514
PAD
SW
PGND
The trip point voltage must be:
A value of 249 Ω was chosen for this design.
2 A / 60 V
D1
COMP
LED1
LED2
LED3
LED4
OVP
R
V
R
ADJ
ADJ
ADJ
= (0.104 (V) – 0.099 (V)) / 20.3 (μA) = 246.31 Ω
= 3.0 (A) × 0.033 (Ω) = 0.099 (V)
= (V
137 kΩ
Fault Tolerant LED Driver
R
OVP
120 pF
SENSEtrip
C
P
10 LEDs each string
4.7 μF
– V
C
V
150 Ω
OUT
R
C
0.47 μF
OUT
Z
Z
115 Northeast Cutoff
1.508.853.5000; www.allegromicro.com
Allegro MicroSystems, Inc.
Worcester, Massachusetts 01615-0036 U.S.A.
ADJ
) / I
ADJ
(typ)
(29)
29