LR8
Typical Application Circuits
*
V
=5.0V
OUT
VIN
VOUT
ADJ
V =15V to 450V
IN
R1
6.04KΩ
±1%
C2
1.0µF
C1
R
LOAD
≤16.5KΩ
R2
18.2KΩ
±1%
R2
R1
V
= 1.20V 1+
+ I R2
ADJ
OUT
Figure 1: High Input Voltage, 5.0V Output Linear Regulator
* Required for conditions where VIN is less than VOUT
.
V =15V to 450V
IN
+
V
Auxiliary
Vout1
-
LR8
VIN
VOUT
+
ADJ
Vout2
-
Vcc
FB
PWM IC
Figure 2: SMPS Start-Up Circuit
1µF
1.20V
R
I
=
LR8
OUT
VIN
VOUT
ADJ
+
R
V
= 15V
to 450V
IN
Load
-
Figure 3: High Voltage Adjustable Constant Current Source
4