TS2938
Taiwan Semiconductor
Document Number: DS_P0000209 4 Version: G15
ORDERING INFORMATION
5.0V
TS2938CS50 RLG SOP-8
2,500pcs / 13” Reel
3.3V
TS2938CS33 RLG SOP-8
2,500pcs / 13” Reel
Note:
1. Compliant to RoHS Directive 2011/65/EU and in accordance to WEEE 2002/96/EC.
2. Halogen-free according to IEC 61249-2-21 definition.
BLOCK DIAGRAM
APPLICATION INFORMATION
The TS2938 series is a high performance with low dropout voltage regulator suitable for moderate to high current
and voltage regulator application. Its 500mV (typ.) dropout voltage at full load and over temperature makes it
especially valuable in battery power systems and as high efficiency noise filters in post regulator applications.
Unlike normal NPN transistor design, where the base to emitter voltage drop and collector to emitter saturation
voltage limit the minimum dropout voltage, dropout performance of the PNP output of these devices is limited
only by low V
CE
saturation voltage.
The TS2938 series is fully protected from damage due to fault conditions. Linear current limiting is provided.
Output current during overload conditions is constant. Thermal shutdown the device when the die temperature
exceeds the maximum safe operating temperature. Transient protection allows device survival even when the
input voltage spikes above and below nominal. The output structure of these regulators allows voltages in excess
of the desired output voltage to be applied without reverse current flow.
Output Capacitor
The TS2938 series requires an output capacitor to maintain stability and improve transient response. Proper
capacitor selection is important to ensure proper operation. The output capacitor selection is dependent upon the
ESR of the output capacitor the maintain stability. When the output capacitor is 6.8µF or greater, the output
capacitor should have an ESR less than 2ohm. This will improve transient response as well as promoted stability.
Ultra low ESR capacitors (<100mohm), such as ceramic chip capacitors may promote instability. These very low
ESR levels may cause an oscillation and/or under damped transient response. A low ESR solid tantalum
capacitor works extremely well and provide good transient response and stability over temperature. Aluminum
electrolytic can also be used, as long as the ESR of the capacitor is <2ohm. The value of the output capacitor
can be increased without limit. Higher capacitance values help to improved transient response and ripple
rejection and reduce output noise.