Datasheet

TL431
V
I(BATT)
R3
(see Note A)
R1A
R4
(see Note A)
R2BR2A
R1B
Low Limit = 1 +
R1B
R2B
V
ref
High Limit = 1 +
R1A
R2A
V
ref
LED on When Low Limit < V
I(BATT)
< High Limit
TL431
12 V
V
CC
5 V
6.8 kΩ
10 kΩ
10 kΩ
0.1%
10 kΩ
0.1%
X
Not
Used
Feedback
TL598
+
−
V
O
≈5 V
TL431
V
I(BATT)
27.4 kΩ
0.1%
R
b
(see Note A)
27.4 kΩ
0.1%
TL431, TL431A, TL431B, TL432, TL432A, TL432B
www.ti.com SLVS543N –AUGUST 2004–REVISED JANUARY 2014
A. R
b
should provide cathode current ≥1 mA to the TL431.
Figure 24. Efficient 5-V Precision Regulator
Figure 25. PWM Converter With Reference
A. Select R3 and R4 to provide the desired LED intensity and cathode current ≥1 mA to the TL431 at the available
V
I(BATT)
.
Figure 26. Voltage Monitor
Copyright © 2004–2014, Texas Instruments Incorporated Submit Documentation Feedback 23
Product Folder Links :TL431 TL431A TL431B TL432 TL432A TL432B