A8499 Datasheet, PDF (1/7 Pages) Allegro MicroSystems – High Voltage Step-Down Regulator

Features and Benefits
▪ 8 to 50 V input range
▪ Integrated DMOS switch
▪ Adjustable fixed off-time
▪ Highly efficient
▪ Adjustable 1.2 to 24 V output
A8499
High Voltage Step-Down Regulator
Description
The A8499 is a step down regulator that will handle a wide
input operating voltage range.
The A8499 is supplied in a low-profile 8-lead SOIC with
exposed pad (package LJ).
Applications include:
▪ Printer power supplies
▪ Consumer equipment power supplies
Package: 8-Lead SOIC with exposed
thermal pad (suffix LJ)
Approximate Scale 1:1
Typical Application
CBOOT
0.01 μF
BOOT
VIN
ENB
RTSET
121 kΩ
TSET
GND
A8499
LX
VBIAS
FB
D1
+42 V
C3
100 μF
50 V
C3
0.22 μF
L1
47 μH
R1
17.8 kΩ
R2
10.2 kΩ
VOUT
3.3 V / 1.2 A
ESR
COUT
220 μF
10 V
90.0
88.0
86.0
84.0
82.0
80.0
78.0
76.0
74.0
72.0
70.0
0
Efficiency vs. Output Current
VOUT (V)
3.3
5
200 400 600 800 1000 1200 1400
I_OUT (mA)
Circuit for 42 V step down to 3.3 V at 1.2 A. Efficiency data from circuit shown in left panel.Data is for reference only.
A8499-DS, Rev. 3