A8518 Datasheet, PDF (9/30 Pages) Allegro MicroSystems – Fully integrated 42 V MOSFET for boost converter

A8518 and A8518-1
Wide Input Voltage Range, High-Efficiency,
Fault-Tolerant LED Driver
V_IN
C_IN
V_C
R_PU
*optional
L1
D1
R_SC
Q1
R_ADJ
R_OVP
GATE
VSENSE
VIN
VDD
SW
VOUT
OVP
C_VDD
A8518
LED1
FAULT
PWM
APWM
ISET
R_ISET
LED2
COMP
AGND PGND
C_P
GND
V_OUT > V_IN
C_OUT1
C_OUT2
R_Z
C_Z
Typical Application Showing Boost Configuration with Input Switch to Protect Against VOUT-to-GND Short
V_IN
C_IN
V_C
R_PU
L1
R1* D2*
L2
D2
C_SW
R_OVP
Output: 3 WLED in series
(~10 V)
C_OUT
GATE
VSENSE
VIN
VDD
SW
VOUT
OVP
C_VDD
LED1
FAULT
PWM
APWM
ISET
R_ISET
GND
LED2
AGND PGND COMP
C_P
R_Z
C_Z
*Notes:
Input disconnect switch is not necessary in this
case to protect against VOUT-to-GND short.
R1 and D2 are used to provide a leakage path
such that OVP pin is above 100 mV during startup;
otherwise, the IC would assume a VOUT-to-GND
short and not proceed with soft start.
Typical Application Showing SEPIC Configuration for Flexible Input/Output Voltage Ratio
Allegro MicroSystems, LLC
9
115 Northeast Cutoff
Worcester, Massachusetts 01615-0036 U.S.A.
1.508.853.5000; www.allegromicro.com