TS19375

PWM Step-Up Controller

4/8

Version: B11

Function Description

PWM Control

The TS19375 is high efficient PWM step-up controller, the pulse width varies in a range from 0 to 85%. According

to the load current, the ripple voltage produced by the switching can easily be removed through a filter because the

switching frequency remains constant. Therefore, TS19375 provide a low-ripple power over broad ranges of input

voltage and load current.

Setting the Output Voltage

Application circuit shows the basic application circuit with adjustable output version. The external resistor sets the

output voltage according to the following formula:

Table 1: Resistor select for output voltage setting

R2

R1

12V

1K

11K

15V

1.5K

21K

18V

1K

17K

24V

1.3K

30K

Current Limit Setting

application circuit). The internal current limit compared voltage is 60mV. When the SENSE voltage is larger than

60mV, an over-current condition is triggered. Please refer to the formula for setting the minimum current limit value:

Inductor Selection

For most designs, Low inductance values are physically smaller but require faster switching, which results in some

efficiency loss. The inductor value can be derived from the following formula:

Large value inductors lower ripple current and small value inductors result in high ripple currents. Choose inductor

ripple current approximately 15% of the maximum input current 3A, ∆IL=0.45A.

9V

12V

15V

18V

L1 Value

18uH

15uH

10uH

10uH

The DC current rating of the inductor should be at least equal to the maximum load current plus half the ripple

current to prevent core saturation (3A+0.25A).