TS5201

200mA Low Noise LDO

Voltage Regulator with Enable

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Version: B07

Application Information (Continue)

No Load Stability

The TS5201 series will remain stable and in regulation with no load, unlike many other voltage regulators. This is

especially important in CMOS RAM keep alive applications.

Adjustable Regulator Design

The adjustable regulator versions can be adjusted to a specific output voltage by using two external resistors to

programming the output voltage anywhere between 1.25 and the 8V maximum operating rating of the family.

Two resistors are used. Resistors can be quite large up to 470kΩ, because of the very high input impedance and low

bias current of the sense comparator, the resistor values are calculated by:

A capacitor from Adjust to Ground provides greatly improved noise performance.

(Adjustable output range up to 8V)

Dual Supply Operation

When used in dual supply systems where the regulator load is returned to a negative supply, the output voltage must

be diode clamped to ground.

Thermal Characteristics

TS5201 series is designed to provide 200mA (5V version) of continuous current in a very small package. Maximum

power dissipation can be calculated based on the output current and the voltage drop across the part. To determine

the maximum power dissipation of the package, use the junction-ambient thermal resistance of the device and the

following basic equation:

layout dependent, the actual power dissipation of the regulator circuit can be determined using the equation:

Substituting Pd(max) for Pd and solving for the operating conditions that are critical to the application will give the

maximum operating conditions for the regulator circuit. For example, when operating the TS5201CS at room

temperature with a minimum footprint layout, the maximum input voltage for a set output current can be determined

as follows:

off

EN

2.2uF

on

R1

R2