logic

out

FB3

FB3

logic

logic

V

R9

R9

R9

V

= V

+ (V

V

)

= 0.75

V

= 2.475V 0.825

R10

4

R10

R10

´

-

´

´

-

-

´

´

(42)

logic

logic

V

0.75

V

0.825 V

R10 =

=

10 k

80 A

80 A

-

´

»

W

m

m

(43)

out

logic

out

FB3

out

FB3

logic

logic

V

0.75

V

V

V

V

2.475 V

R9 =

R10 =

R10 =

R10

V

V

0.25

V

0.825 V

-

´

-

-

´

´

´

-

-

´

-

(44)

(

)

(

dis

OFFE

SS

SS

dis

logic

dis

R

R9 + R10)

(V

V

R11 =

V

R

R9 + R10) V

R

´

´

-

´

+

-

´

(45)

Base1

FB3

Error Amplifier

¾Vref

5mA

max.

VSNS

Output Capacitor Selection (Negative Shunt Regulator)

TPS65166

50

µA through the feedback divider provides good accuracy. Be aware of the negative value of V

calculations.

the calculated R11 = 4.98k

Ω and the resistor values 4.7kΩ, 4.3kΩ, and 4.0kΩ can be used.

Figure 32. Negative Shunt Regulator Block Diagram

For the best output voltage filtering, low ESR ceramic output capacitors are recommended. One 1

µF ceramic

output capacitor with a sufficient voltage rating is suitable for most applications. See Table 15 for output capacitor

selection.

Table 15. Output Capacitor Selection (Negative Shunt Regulator)

CAPACITOR

COMPONENT SUPPLIER

1

µF/25V

Murata, GRM21BR71E105KA99

1

µF/50V

Taiyo Yuden, UMK325BJ105KH

32

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