65052 datasheet(25/41 Pages) TI

25 / 41 page

www.ti.com

APPLICATION INFORMATION

Output Voltage Setting

Converter 1 (DCDC1)

x1+

ref

()

(4)

Converter 2 (DCDC2)

VINDCDC1/2

ENDCDC2

PGND

VDCDC2

Vbat

1 W

DEFDCDC2

AGND

TPS65050, TPS65051, TPS65052

TPS65054, TPS65056

SLVS710 – JANUARY 2007

The output voltage of converter 1 can be set by an external resistor network. The output voltage can be

calculated using Equation 4.

with an internal reference voltage Vref, 0.6 V .

Setting the total resistance of R1 + R2 to less than 1 M

Ω is recommended. The resistor network connects to the

input of the feedback amplifier, therefore, requiring a small feedforward capacitor in parallel to R1. A typical

value of 47 pF is sufficient.

The output voltage of converter 2 can be selected as following:

• Adjustable output voltage defined with external resistor network on pin DEFDCDC2. This option is available

for TPS65050 and TPS65051.

• Two default fixed output voltages selectable by pin DEFDCDC2, see Table 2. This option is available for

TPS65052 and TPS65054.

Table 2. Default Fixed Output Voltages

Converter 2

DEFDCDC2 = low

DEFDCDC2 = high

TPS65050

TPS65051

TPS65052

1 V

1.3 V

TPS65054

1.3 V

1.05 V

TPS65056

1 V

1.3 V

The adjustable output voltage can be calculated similar to the DCDC1 converter. Setting the total resistance of

R3 + R4 to less than 1 M

Ω is recommended. Route the DEFDCDC2 line separate from noise sources, such as

the inductor or the L2 line. The VDCDC2 line needs to be directly connected to the output capacitor. As the

VDCDC2 line is the feedback to the internal amplifier, no feedforward capacitor at R3 is needed.

Using an external resistor divider at DEFDCDC2:

Figure 23. External Resistor Divider

Submit Documentation Feedback

65052 Datasheet(PDF) 25 Page - Texas Instruments

65052 Datasheet(HTML) 25 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41

Datasheet Download

Link URL