TAR5S15U~TAR5S50U

2003-02-10

6

3.

Ripple Rejection

The devices of the TAR5SxxU Series feature a circuit with an excellent ripple rejection characteristic.

Because the circuit also features an excellent output fluctuation characteristic for sudden supply voltage drops,

the circuit is ideal for use in the RF blocks incorporated in all mobile telephones.

4.

NOISE Pin

TAR5SxxU Series devices incorporate a NOISE pin to reduce output noise voltage. Inserting a capacitor

between the NOISE pin and GND reduces output noise. To ensure stable operation, insert a capacitor of

0.0047

µF or more between the NOISE pin and GND.

The output voltage rise time varies according to the capacitance of the capacitor connected to the NOISE

pin.

Ripple Rejection

− f

TAR5S28U Input Transient Response

Frequency

f

(Hz)

Time

t

(ms)

0

10

100

1 k

10 k

100 k 300 k

10

20

30

40

50

60

70

80

10

µF

2.2

µF

1

µF

VIN = 4.0 V, CNOISE = 0.01 µF,

CIN = 1 µF, Vripple = 500 mVp

−p,

Iout = 10 mA, Ta = 25°C

Turn On Waveform

NOISE capacitance

CNOISE (F)

Time

t

(ms)

0

10

20

30

40

50

60

0.001

µ

0.01

µ

1.0

µ

TAR5S50

0.1

µ

TAR5S30

TAR5S15

CIN = 1 µF, Cout = 10 µF,

Iout = 10 mA, Ta = 25°C

01

45

8

10

Input voltage

2.8 V

2

3

6

7

9

Output voltage

3.1 V

3.4 V

Ta

= 25°C, CIN = 1 µF,

Cout = 10 µF, CNOISE = 0.01 µF,

VIN: 3.4 V → 3.1 V, Iout = 50 mA

40

10

20

0

1

2

3

1

2

−10

0

90

30

0

60

50

80

70

Output voltage waveform

Control voltage waveform

CNOISE = 0.01 µF

1

µF

0.33

µF

0.1

µF

CIN = 1 µF, Cout = 10 µF,

Iout = 50 mA, Ta = 25°C