TS2938

Taiwan Semiconductor

Document Number: DS_P0000209

5

Version: G15

APPLICATION INFORMATION (CONTINUED)

Minimum Load Current

The TS2938 series is specified between finite loads. If the output current is too small leakage currents dominate

and the output voltage rises. A 5mA minimum load current is necessary for proper regulation.

Input Capacitor

An input capacitor of 1µF or greater is recommended when the device is more that 4 inches away from the bulk

AC supply capacitance or when the supply is a battery. Small and surface mount ceramic chip capacitors can be

used for bypassing. Larger values will help to improve ripple rejection by bypassing the input to the regulator,

further improving the integrity of the output voltage.

Thermal Characteristics

A heatsink may be required depending on the maximum power dissipation and maximum ambient temperature of

the application. Under all possible operating conditions, the junction temperature must be within the range

specified under absolute maximum ratings. To determine if the heatsink is required, the power dissipated by the

= 400mW + 36mW

= 436mW

The next parameter which must be calculated the maximum allowable temperature rise.

θ

Inhibit Input

TS2938 feature an active-low (Inhibit) input that allows ON/OFF control of the regulator. The Inhibit input has

TTL/CMOS compatible thresholds for simple interfacing with logic interfacing. Inhibit should be directly tied to

Ground or keep open (not connected).