V

1 )

R1

R2

R1 +

V

OUT

V

REF

* 1

R2

OUTPUT VOLTAGE

PROGRAMMING GUIDE

OUTPUT

VOLTAGE

R1

R2

1.8 V

2.8 V

5.0 V

392 M

Ω

1.07 M

Ω

2.55 M

Ω

806 k

Ω

806 k

Ω

806 k

Ω

FB

R1

R2

GND

IN

TPS715A01

0.1

µF

0.47

µF

OUT

TPS715Axx

SBVS047E

– MAY 2004 – REVISED JUNE 2011

www.ti.com

Programming the TPS715A01 Adjustable LDO Regulator

The output voltage of the TPS715A01 adjustable regulator is programmed using an external resistor divider as

shown in Figure 15. The output voltage is calculated using Equation 3:

(3)

where:

Resistors R1 and R2 should be chosen for approximately 1.5

μA divider current. Lower value resistors can be

used for improved noise performance, but the solution consumes more power. Higher resistor values should be

avoided as leakage current into/out of FB across R1/R2 creates an offset voltage that artificially

design procedure is to choose R2 = 1M

Ω to set the divider current at 1.5μA, and then calculate R1 using

Equation 4:

(4)

Figure 15. TPS715A01 Adjustable LDO Regulator Programming

8

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© 2004–2011, Texas Instruments Incorporated