BAYLI B4251CK5-6.0, B4251CK5-5.9, B4251CK-4.8, B4251CK-4.7, B4251CK-4.6 Datasheet

Bay Linear, Inc

2478 Armstrong Street, Livermore, CA 94550 Tel: [phone], Fax: [phone] www.baylinear.com

250mA Low Dropout Voltage Regulators

B4251

ON/OFF & BYPASS

Pin Connection

Ordering Information

Package Part No.

SOT-25 B4251CK5-X.X

SOT-89 B4251CR-X.X

X.X = Fixed Output Voltages from 2.0V to 6.0V

ON/OFF (Enable) Function

Part No ON/Off V

OUT

High ON

B4251

Low OFF

Description

The B4251 series are a group of positive output voltage,
five-pin regulators, which provide a high current even
when the input/output voltage differential is small. Low
power consumption and high accuracy is achieved
though CMOS and programmable fuse technologies.
Output voltage: 2.0V to 6.0V in 0.1V increments.

The B4251 consists of a high-precision voltage
reference, an error correction circuit, and a current
limited output driver. Key features include a Shutdown
Pin that reduces supply current to 0.5µA max and a
470pF Bypass input to ground reduces noise present on
the internal reference, which in turn significantly reduce
output noise. If output noise is not concern, this input
maybe left unconnected. Larger capacitor values cap be
used, but results in longer time period to rated output
voltage when power initially applied.

The ON/OFF pin enables the output to be turned off,
resulting in reduced power consumption. Provided in
SOT-25 (150mW) packages minimizes the usage of

b

oard real state.

Features

• Maximum Output Current: 250 mA.

• Highly Accurate Output Voltage +/- 1.4%

• Only 19µA Power Consumption MAX

• Shutdown Supply Current 1µA

• Ground Current of Less than 5µA

• Very Low Dropout

0.12V at 100mA

0.23V at 250mA

• Shutdown Mode for Power Savings

• With ON/OFF & BYPASS Features

• Offered in SOT-89 & SOT-25 Packages

• PIN-to-PIN S-818

Applications

• Battery Powered Equipment

• Notebook PC, Palmtops, PDA

• Portable Cameras and Video Recorders

• Reference Voltage Sources

• Cellular / GSM / PCS Phones

Bay Linear

Inspire the Linear Power

SOT-89 (R)

Top View

On/OffV

in

Vss

3

21

4

5

V

out

NC

SOT-25 (K5)

Top View

ON/OFF

V

in

GND

32

1

45

V

out

Bypass

Bay Linear, Inc

2478 Armstrong Street, Livermore, CA 94550 Tel: [phone], Fax: [phone] www.baylinear.com

B4251

Absolute Maximum Ratings

Parameter Symbol Ratings Units

Input Voltage VIN 12 V
Output Current I

OUT

500 mA

Output Voltage V

OUT

V

SS

-0.3 to VIN 0.3 V

On/Off Voltage On/Off VSS -0.3 to V

IN+

0.3 V

Continual Total Power Dissipation SOT-25

SOT-89

Pd

150
300

mW

Operating Ambient Temperature T

OPR

-30 to 80

°C

Storage Temperature T

STG

-40 to 125

°C

Electrical Characteristics (Ta = 25°C, V

IN

= V

OUT +

0.5V; unless otherwise noted)

Parameter Conditions MIN TYP MAX UNIT

IO = 1mA -1.4% - +1.4%

Output Voltage Accuracy

I

O

= 0 to 150mA -2% - +2%

V

Line Regulation
∆V

OUT

/∆VIN-V

OUT

I

O

= 100mA,

(V

OUT

+ 0.1V)<VIN<6V

0.2 0.3 %/V

Load Regulation

VIN 6V, 0mA < I

O

< 120mA C

OUT

= 1µF

0.01

0.04 %/mV

Maximum Output Current 250
Current Limit 160 500

mA

Shutdown Supply Current

T

A

=25°C

0.01 1

µA

Shutdown Input Bias Current

VSHDN=V

IN, TA

=25°C

0.01 100

nA

Shutdown Exit Delay

CBP=0µF C

OUT

=1µF, IO = 1mA

30 150

µsec
Shutdown Input Threshold Low Vin=2.5 to 5.5V 0.4 V
Shutdown Input Threshold High Vin=2.5 to 5.5V 2 V
Ground Pin Current I

OUT

= 0mA……150mA

2 5

µA

IO = 150mA 160 250

Dropout Voltage

I

O

= 250 mA

200 280

mV

Thermal Shutdown Temperature

155

°C

Marking Format

SOT-25

FXWW

F = B4251

Variables

X = Voltage Codes WW = Work Week Code

B = 2.0 F = 3.3

SOT-25 = 01 to 99

C = 2.5 G = 3.5

D = 2.8 H = 5.0

E = 3.0