Linear Technology LT1312CS8 Datasheet

LT1312

Single PCMCIA

OBSOLETE:

FOR INFORMATION PURPOSES ONLY

Contact Linear Technology for Potential Replacement

FEATURES

■

Digital Selection of 0V, VCC, 12V or Hi-Z

■

120mA Output Current Capability

■

Internal Current Limiting and Thermal Shutdown

■

Automatic Switching from 3.3V to 5V

■

Powered from Unregulated 13V to 20V Supply

■

Logic Compatible with Standard PCMCIA Controllers

■

1µF Output Capacitor

■

30µA Quiescent Current in Hi-Z or 0V Mode

■

VPP Valid Status Feedback Signal

■

No VPP Overshoot

■

8-Pin SO Packaging

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APPLICATIONS

■

Notebook Computers

■

Palmtop Computers

■

Pen-Based Computers

■

Handi-Terminals

■

Bar-Code Readers

■

Flash Memory Programming

VPP Driver/Regulator

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DESCRIPTION

The LT®1312 is a member of Linear Technology
Corporation’s family of PCMCIA drivers/regulators. The
LT1312 provides 0V, 3.3V, 5V, 12V and Hi-Z regulated
power to the VPP pin of a PCMCIA card slot from a single
unregulated 13V to 20V supply. When used in conjunction
with a PC card interface controller, the LT1312 forms a
complete minimum component-count interface for palm­top, pen-based and notebook computers. The VPP output
voltage is selected by two logic compatible digital inputs
which interface directly with industry standard PC card
interface controllers.

Automatic 3.3V to 5V switching is provided by an internal
comparator which continuously monitors the PC card V
supply and automatically adjusts the regulated VPP out­put to match VCC when the VPP = VCC mode is selected.

An open-collector VPP VALID output is driven low when
VPP is in regulation at 12V.

The LT1312 is available in an 8-pin SO package.

, LTC and LT are registered trademarks of Linear Technology Corporation.

CC

TYPICAL APPLICATION

Typical PCMCIA Single Slot VPP Driver

13V TO 20V

V

S

VPP

PCMCIA

CARD SLOT

CONTROLLER

LT1312 TRUTH TABLE

EN0 EN1 SENSE VPP

00 X 0V 1
1 0 X 12V 0
0 1 3.0V TO 3.6V 3.3V 1
0 1 4.5V TO 5.5V 5V 1
1 1 X Hi-Z 1

X = DON’T CARE

EN0

VALID SENSE

LT1312EN1

GND

OUT

+

C
1µF
TANTALUM

U

3.3V OR 5V

OUT

OUT

VPP1

VPP2

PCMCIA

CARD SLOT

V

CC

VALID

LT1312 TA1

Linear Technology PCMCIA Product Family

DEVICE DESCRIPTION PACKAGE

LT1312 SINGLE PCMCIA VPP DRIVER/REGULATOR 8-PIN SO

LT1313 DUAL PCMCIA VPP DRIVER/REGULATOR 16-PIN SO*

LTC®1314 SINGLE PCMCIA SWITCH MATRIX 14-PIN SO

LTC1315 DUAL PCMCIA SWITCH MATRIX 24-PIN SSOP

LTC1470 PROTECTED VCC 5V/3.3V SWITCH MATRIX 8-PIN SO

LTC1472 PROTECTED VCC AND VPP SWITCH MATRIX 16-PIN SO*

*NARROW BODY

1

LT1312

1

2

3

4

8

7

6

5

TOP VIEW

S8 PACKAGE

8-LEAD PLASTIC SO

GND

ENO

EN1

VALID

VPP

OUT

N.C.
V

S

SENSE

WW

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ABSOLUTE MAXIMUM RATINGS

Supply Voltage ........................................................ 22V

Digital Input Voltage ........................ 7V to (GND – 0.3V)

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PACKAGE/ORDER INFORMATION

ORDER PART

NUMBER

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Sense Input Voltage......................... 7V to (GND – 0.3V)

Valid Output Voltage ...................... 15V to (GND – 0.3V)

LT1312CS8

Output Short-Circuit Duration.......................... Indefinite

Operating Temperature ................................ 0°C to 70°C

S8 PART MARKING

Junction Temperature................................ 0°C to 125°C

Storage Temperature Range ..................–65°C to 150°C

T

= 125°C, θJA = 150°C/W

JMAX

1312

Lead Temperature (Soldering, 10 sec).................. 300°C

Consult factory for Industrial and Military grade parts.

ELECTRICAL CHARACTERISTICS

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

VPP

OUT

I

LKG

I

S

I

LIM

V

ENH

V

ENL

I

ENH

I

ENL

V

SEN5

V

SEN3

I

SEN

V

VALID TH

I

VALID

The ● denotes the specifications which apply over the full operating
temperature range.

Output Voltage Program to 12V, I

Program to 5V, I
Program to 3.3V, I
Program to 0V, I

Output Leakage Program to Hi-Z, 0V ≤ VPP
Supply Current Program to 0V ● 30 50 µA

Program to Hi-Z
Program to 12V, No Load
Program to 5V, No Load
Program to 3.3V, No Load
Program to 12V, I
Program to 5V, I
Program to 3.3V, I

Current Limit Program to 3.3V, 5V or 12V 330 500 mA
Enable Input High Voltage ● 2.4 V
Enable Input Low Voltage ● 0.4 V
Enable Input High Current 2.4V ≤ VIN ≤ 5.5V 20 50 µA
Enable Input Low Current 0V ≤ VIN ≤ 0.4V 0.01 1 µA
VCC Sense Threshold VPP
VCC Sense Threshold VPP
VCC Sense Input Current V

VPP
VPP
VPP

Threshold Voltage Program to 12V ● 10.5 11 11.5 V

VALID

Output Drive Current Program to 12V, V

VALID

Output Leakage Current Program to 0V, V

VALID

OUT

OUT

= 5V 38 60 µA

SENSE

V

= 3.3V 18 30 µA

SENSE

VS = 13V to 20V, TA = 25°C, unless otherwise noted.

≤ 120mA (Note 1) ● 11.52 12.00 12.48 V

OUT

≤ 30mA (Note 1) ● 4.75 5.00 5.25 V

OUT

≤ 30mA (Note 1) ● 3.135 3.30 3.465 V

OUT

= –300µA 0.42 0.60 V

OUT

≤ 12V ● –10 10 µA

OUT

● 30 50 µA

● 230 360 µA

● 75 120 µA

● 55 90 µA

= 120mA ● 126 132 mA

OUT

= 30mA ● 31 33 mA

OUT

= 30mA ● 31 33 mA

OUT

= 3.3V to 5V ● 3.60 4.05 4.50 V
= 5V to 3.3V ● 3.60 4.00 4.50 V

= 0.4V 1 3.3 mA

VALID

= 12V 0.1 10 µA

VALID

Note 1: For junction temperatures greater than 110°C, a minimum load
of 1mA is recommended.

2

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TYPICAL PERFORMANCE CHARACTERISTICS

LT1312

Quiescent Current (12V Mode)Quiescent Current (0V or Hi-Z Mode)

50

TJ = 25°C
EN0 = EN1= 0V
OR

40

EN0 = EN1= 5V

30

20

QUIESCENT CURRENT (µA)

10

0

5

0

10

SUPPLY VOLTAGE (V)

15

20

25

LT1312 G1

500

TJ = 25°C
EN0 = 5V
EN1 = 0V

400

=

∞

R

L

300

200

QUIESCENT CURRENT (µA)

100

0

5

0

SUPPLY VOLTAGE (V)

15

10

Ground Pin Current (12V Mode) Ground Pin Current (5V Mode)

10

TJ = 25°C
EN0 = 5V
EN1 = 0V

8

6

4

GROUND CURRENT (mA)

2

0

5

0

SUPPLY VOLTAGE (V)

R

L

I

= 60mA*

L

R

L

= 30mA*

I

L

*FOR VPP

10

= 100

R

L

= 120mA*

I

L

= 200

= 400

15

Ω

Ω

OUT

Ω

= 12V

20

25

LT1312 G4

2.5
TJ = 25°C
EN0 = 0V
EN1 = 5V

2.0

1.5

1.0

GROUND CURRENT (mA)

0.5

0

= 5V

V

SENSE

5

0

SUPPLY VOLTAGE (V)

R

L

I

L

R

= 500Ω

L

= 10mA*

I

L

*FOR VPP

10

= 167Ω

= 30mA*

15

OUT

= 5V

Quiescent Current (3.3V/5V Mode)

250

TJ = 25°C
EN0 = 0V
EN1 = 5V

200

=

∞

R

L

150

100

QUIESCENT CURRENT (µA)

50

20

25

LT1312 G2

0

5

0

V

= 5V

SENSE

V

= 3.3V

SENSE

15

10

SUPPLY VOLTAGE (V)

20

25

LT1312 G3

Ground Pin Current (3.3V Mode)

2.5
TJ = 25°C
EN0 = 0V
EN1 = 5V

2.0

1.5

1.0

GROUND CURRENT (mA)

0.5

20

25

LT1312 G5

0

= 3.3V

V

SENSE

= 110

Ω

R

L

I

= 30mA*

L

R

= 330

Ω

L

= 10mA*

I

L

*FOR VPP

5

0

10

SUPPLY VOLTAGE (V)

= 3.3V

OUT

15

20

25

LT1312 G6

Ground Pin Current

16

TJ = 25°C

= 15V

V

14

S

12

10

8

6

4

GROUND PIN CURRENT (mA)

2

0

0

20

60

40

OUTPUT CURRENT (mA)

Current Limit

800

TJ = 25°C

= 0V

VPP

700

600

500

400

300

200

SHORT-CIRCUIT CURRENT (mA)

100

100

80

120

140

LT1312 G7

160

OUT

0

510 20

0

INPUT VOLTAGE (V)

15

25

LT1312 G8

Current Limit

600

VS = 15V

= 0V

VPP

OUT

500

400

300

200

SHORT-CIRCUIT CURRENT (mA)

100

0

25 50 75 100

0

JUNCTION TEMPERATURE (°C)

125

LT1312 G9

3

LT1312

TIME (ms)

–0.1 0 0.1 0.2 0.3 0.4 0.5 0.6

OUTPUT VOLTAGE

CHANGE (V)

LOAD

CURRENT (mA)

50

–0.4

0.4

LT1312 G18

100

–0.2

0

0.2
C

OUT

= 1µF

C

OUT

= 10µF

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TYPICAL PERFORMANCE CHARACTERISTICS

3.0
VS = 15V

2.5

2.0

1.5

1.0

0.5

INPUT THRESHOLD VOLTAGE (V)

0

25 50 75 100

0

JUNCTION TEMPERATURE (°C)

VCC Sense Input Current

50

TJ = 25°C
V

= 15V

S

40

30

20

LT1312 G10

125

Enable Input CurrentEnable Input Threshold Voltage

50

TJ = 25°C
V

= 15V

S

40

30

20

ENABLE INPUT CURRENT (µA)

10

0

0

234

1

ENABLE INPUT VOLTAGE (V)

VALID Output Voltage

1.0
TJ = 25°C

V

= 15V

S

EN0 = 5V

0.8

EN1 = 0V

0.6

0.4

56

LT1312 G11

VCC Sense Threshold Voltage

5.5
TJ = 25°C

= 15V

V

S

5.0

4.5

4.0

3.5

SENSE THRESHOLD VOLTAGES (V)

3.0

CC

V

2.5

0

SWITCH TO 5V

SWITCH TO 3.3V

25 50 75 100

JUNCTION TEMPERATURE (°C)

Ripple Rejection (12V)

100

TJ = 25°C, 12V MODE

80

60

40

= 15V + 100mV

V

S

RIPPLE

RMS

C

= 1µF TANTALUM

OUT

125

LT1312 G12

SENSE INPUT CURRENT (µA)

CC

V

12.4

12.2

12.0

11.8

OUTPUT VOLTAGE (V)EN0 INPUT (V)

11.6

10

0

0

234

1

ENABLE INPUT VOLTAGE (V)

56

LT1312 G13

12V Turn-On Waveform

VS = 15V

C

= 1µF

OUT

5

0

–0.2 0 0.2 0.4 0.6 0.8 1.0 1.2

TIME (ms)

C

= 10µF

OUT

LT1312 G16

VALID OUTPUT VOLTAGE (V)

0.2

0

0

1.0 1.5 2.0

0.5
VALID OUTPUT CURRENT (mA)

Line Transient Response (12V)

40

20

0

–20

CHANGE (mV)

OUTPUT VOLTAGE

–40

15

SUPPLY

13

VOLTAGE (V)

–0.1 0 0.1 0.2 0.3 0.4 0.5 0.6

C

OUT

C

OUT

= 10µF

TIME (ms)

= 1µF

2.5 3.0

LT1312 G14

LT1312 G17

20

RIPPLE REJECTION RATIO (dB)

0

100 1k 10k 100k 1M

10

FREQUENCY (Hz)

Load Transient Response (12V)

LT1312 G15

4