TS5205 series

1-6

2004/09 rev. A

TS5205

150mA Low Noise LDO Voltage Regulator with Enable

Low Power Consumption

Low DropOut Voltage 0.275V

Fixed and Adjustable Output

Enable Shutdown

General Description

The TS5205 series is an efficient linear voltage regulator with ultra low noise output, very low dropout voltage (typically
17mV at light loads and 165mV at 150mA), and very low power consumption (600uA at 100mA), providing high output
current even when the application requires very low dropout voltage. The Chip Enable (CE) includes a CMOS or TTL
compatible input allows the output to be turned off to prolong battery life. When shutdown, power consumption drops
nearly to zero.
The TS5205 series is included a precision voltage reference, error correction circuit, a current limited output driver, over
temperature shutdown, revered battery protection and a reference bypass pin to improve its already excellent low-noise
performance.
The TS5205 series is available in fixed and adjustable output voltage version in 5-pin SOT-25 package.

Features

Ultra low noise output.

Output current up to 150mA

Low dropout voltage

Low power consumption

"Zero" off-mode current

Logic controlled electronic enable

Internal current limit and Thermal shutdown protection

Applications

Cellular telephones

Palmtops, notebook computers

Battery powered equipment

Consumer and personal electronics

SMPS post regulator and DC to DC modules

High-efficiency linear power supplies

Ordering Information

Note: Where xx denotes voltage option, available are

5.0V, 3.3V, 3.0V, 2.9V, 2.8V, 2.5V and 1.8V. Leave
blank for adjustable version. Contact factory for
additional voltage options.

Part No.

Operating Temp. Package

TS5205CX5xx

-40 ~ +125

C SOT-25

Typical Application Circuit

Pin assignment
1. Input
2. Ground
3. Enable
4. Bypass / Adjust
5. Output

TS5205 series

2-6

2004/09 rev. A

Absolute Maximum Rating

(Note 1)

Input Supply Voltage

Vin

-20~ +20

Enable Input Voltage

Vce

-20~ +20

Power Dissipation (Note 2)

Internal limited

Thermal Resistance

ja 220

C/W

Operating Junction Temperature Range

-40 ~ +125

Storage Temperature Range

STG

-65 ~ +150

Lead Soldering Temperature (260

Recommend Operating Rating

(Note 3)

Input Supply Voltage

Vin

+2.5 ~ +16

Enable Input Voltage

Vce

0 ~ Vin

Electrical Characteristics

Vin=Vo+1V, Io=100uA, Cout=1uF, Vce

2V, Tj = 25

C, unless otherwise specified.

Parameter Conditions

Min

Typ

Max

Unit

Output Voltage

Vin=Vo + 1V

0.99|Vo| Vout 1.01|Vo| V

Output Voltage Temp. Coefficient (Note 4)

ppm/

Line Regulation

Vo+1V

Vin 16V

0.005

0.05

%/V

Load Regulation (Note 5)

0.1mA

Io 150mA

0.02

0.2

%/V

Io=100uA --

Io=50mA --

110

150

Io=100mA --

140

250

Dropout Voltage (Note 6)

Io=150mA --

165

275

Quiescent Current

Vin

0.4V (shutdown)

Vin

0.18V (shutdown)

0.01

Io=100uA --

80 125

Io=50mA -- 350 600

Io=100mA

-- 600

1000

Ground Pin Current (Note 7)

Vce

Io=150mA

-- 1300

1900

Output Current Limit

Vout=0V

300

500

Power Supply Rejection Ratio

At f=100Hz, Io=100uA,

Thermal Regulation (Note 8)

0.05

%/W

Output Noise

Io=50mA, Cout=2.2uF,

470pF from bypass to Ground

-- 260 --

nVHz

Enable function

Enable Input Logic-Low Voltage

Regulation shutdown

0.4

Enable Input Logic-High Voltage Regulation

enable

2.0

0.4V

0.01

-1

Enable Input Current

2.0

V --

TS5205 series

3-6

2004/09 rev. A

Electrical Characteristics (continued)

Note 1: Exceeding the absolute maximum rating may damage the device.
Note 2: The maximum allowable power dissipation at any Ta is Pd(max) = [ Tj(max) - Ta] + ja. Exceeding the

maximum allowable power dissipation will result in excessive die temperature, and the regulator will go into
thermal shutdown.

Note 3: The device is not guaranteed to function outside its operating rating.
Note 4: Output voltage temperature coefficient is defined as the worst case voltage change divided by the total

temperature range.

Note 5: Regulation is measured at constant junction temperature using low duty cycle pulse testing. Parts are tested

for load regulation in the load range from 1mA to 150mA. Changes in output voltage due to heating effects
are covered by the thermal regulation specification.

Note 6: Dropout voltage is defined as the input to output differential at which the output voltage drops 2% below its

nominal value measured at 1V differential.

Note 7: Ground pin current is the regulator quiescent current plus pass transistor base current. The total current

drawn from the supply is the sum of the load current plus the ground pin current.

Note 8: Thermal regulation is defined as the change in output voltage at a time "t" after a change in power dissipation

is applied, excluding load or line regulation effects. Specifications are for a 150mA load pulse at Vin=16V for
t=10mS.

Block Diagrams

TS5205 series

4-6

2004/09 rev. A

Application Information

Enable Input

TS5205 series feature an active-high (>2V) enable (EN)
input that allows ON/OFF control of the regulator.
Current drain reduces to "zero" when the device is
shutdown, with only micro-amperes of leakage current.
The EN is compatible with CMOS logic interfacing. EN
may be directly tied to Vin and pulled up to the
maximum supply voltage.

Input Capacitor Requirement

An input capacitor of 1uF or greater is recommended
when the device is more than 10" away from the bulk
AC supply capacitance or when the supply is a battery.

Reference Bypass Capacitor

Bypass is connected to the internal voltage reference. A
470uF capacitor (Cbypass) connected from Bypass to
Ground quiets this reference, providing a significant
reduction in output noise. Cbypass reduces the
regulator phase margin; when using Cbypass, output
capacitors of 2.2uF or greater are generally required to
maintain stability.
The star up speed of the TS5205 is inversely
proportional to the size of the reference bypass
capacitor. Applications requiring a slow ramp up of
output voltage should consider larger values of
Cbypass. Likewise, if rapid turn on is necessary,
consider omitting Cbypass. If output noise is not a
major concern, omitted Cbypass and leave Bypass
open.

Output Capacitor Requirement

The TS5205 series requires an output capacitor to
maintain stability and improve transient response is
necessary. The value of this capacitor is dependent
upon whether a reference bypass capacitor is used.
1uF minimum is recommended when Cbypass is not
used. 2.2uF minimum is recommended when Cbypass
is 470uF. Larger values improve the regulator's
transient response. The output capacitor value may be
increased without limit.
The output capacitor should have an ESR (effective
series resistance) less than 5 and a resonant
frequency above 1MHz. Ultra low ESR capacitors can
cause a low amplitude oscillation on the output and/or
under damped transient response.

Most of tantalum or aluminum electrolytic capacitors
are adequate; film types will work. Since many
aluminum electrolytic have electrolytes that freeze at
about �30

C, solid tantalums are recommended for

operation below �25

C. At lower values of output

current, less output capacitance is required for output
stability. The capacitor can be reduced to 0.47uF for
current below 10mA or 0.33uF for currents below 1mA.

No Load Stability

The TS5205 series iwill 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 16V maximum operating rating of the
family.
Two resistors are used. Resistors can be quite large
up to 470k, because of the very high input
impedance and low bias current of the sense
comparator, the resistor values are calculated by:

Vout = 1.242V * (R2 / R1 + 1)

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

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.

TS5205 series

5-6

2004/09 rev. A

Application Information (continues)

Thermal Characteristics

TS5205 series is designed to provide 150mA 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:

Pd(max) = [ Tj(max) � Ta ] /ja

Tj(max) is the maximum junction temperature of the
die(125

C), and Ta is the ambient operating

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

Pd = ( Vin � Vout ) * Iout + Vin * Ignd

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
TS5205CX533 at room temperature with a minimum
footprint layout, the maximum input voltage for a set
output current can be determined as follows:
Pd(max) = (125

C � 25

C) / 220

C/W

Pd(max) = 455mW

The junction to ambient thermal resistance for the
minimum footprint is 220

C/W, the maximum power

dissipation must not be exceeded for proper operation.
Using the output voltage of 3.3V and an output current
of 150mA, the maximum input voltage can be
determined. Formt eh electrical characteristics table,
the maximum ground current for 150mA output current
is 2.5mA.
445mW = ( Vin � 3.3V ) * 150mA + Vin * 2.5mA
445mW = Vin * 150mA � 3.3 * 150mA + Vin * 2.5mA
445mW = Vin * 150mA � 495mW + Vin * 2.5mA
950mW = Vin * 152.5mA
Vin(max) = 6.23v

Therefore, a 3.3V application at 150mA of output
current can accept a maximum input voltage of 6.23V
in a SOT-25 package.

Fixed Output Regulator Application

Ultra Low Noise Fixed Voltage Application

Includes a 470uF capacitor for low noise operation and
shows EN connected to IN for an application where
enable/shutdown is not required. Cout= 2.2uF
minimum.

Low Noise Fixed Voltage Application

An example of a low noise configuration where Cbypass
is not required. Cout= 1uF minimum

Электронный компонент: TS5205CX52.8