TS2950ACT datasheet(5/10 Pages) TSC

5 / 10 page

TS2950/TS2951

150mA Ultra Low Dropout Voltage Regulator

5/10

Version: A07

Application Hints (continued)

Figure 1. Error Output Timing

Programming The output Voltage

The TS2951/A output voltage is programmable for any value from it reference voltage of 1.235V and it maximum rating

of 30V. For example for 5 volt needs to pin-strapped and using the internal voltage divider by tying pin 1 to 2 and pin 7

to pin 6. Refer to Figure 2, there are two external resistor required for this programming. Refer to the below equation

for the programming the output voltage:

Volt=Vref x (1+R1\R2)+IFB * R1

The Vref is 1.235V and IFB is the feedback bias current, nominally -20nA. The minimum recommended load current of

1uA forces an upper limit of 1.2MΩon value of R2, If no load presented the IFB produces error of typically 2% in Vout

which maybe eliminated at room temperature by trimming R1. To improve the accuracy chooses the value of R2=100K

and this reduces the error by 0.17% and increases the resistor program current by 12uA. The TS2951/A typically draw

60uA at no load with pin 2 open-circuit, and this value does not look much.

Figure 2. Adjust Voltage

TS2950ACT Fiches technique(PDF) 5 Page - Taiwan Semiconductor Company, Ltd