LTC1844 Series - 150mA, Micropower, Low Noise, VLDO Linear ...

U U

FEATURES

Very Low Dropout: 90mV at 150mA 30mV at 50mA (LTC1844-3.3)

Wide Input Voltage Range: 1.6V to 6.5V Low 35?A Supply Current, Even in Dropout Low Noise: 60?VRMS (10Hz to 100kHz) ?1.75% Voltage Accuracy Over Temperature,

Voltage and Current Ranges Fast Transient Response 10nA Supply Current in Shutdown Fixed Output Voltages: 1.5V, 1.8V, 2.5V, 2.8V, 3.3V Adjustable Output Voltage: 1.25V to 6V Output Current Limit Reverse-Battery and Reverse-Current Protection No Protection Diodes Needed Stable with 1?F Output Capacitor Stable with Ceramic Capacitors Short-Circuit and Thermal Overload Protection Low Profile (1mm) SOT-23 Package

U APPLICATIO S

Portable Instruments and Battery-Powered Systems Bluetooth/802.11 Cards Cellular Phones PDAs and Notebook Computers

LTC1844 Series

150mA, Micropower, Low Noise, VLDO Linear Regulator

DESCRIPTIO

The LTC?1844 Series are low noise VLDOTM (very low dropout) linear regulators designed for low power/portable applications. These regulators can operate from input voltages as low as 1.6V. Typical output noise is only 30?VRMS and typical dropout for the LTC1844-3.3 is just 90mV at the maximum load current of 150mA, reducing to 30mV at 50mA.

The internal P-channel MOSFET pass transistor requires no base current, allowing the device to draw only 35?A during normal operation, independent of the dropout voltage and load current. The quiescent current falls to a negligible 10nA during shutdown.

Other features include high output voltage accuracy, excellent transient response, stability with ultralow ESR ceramic capacitors as small as 1?F, reverse-battery and reverse-current protection, short-circuit and thermal overload protection and output current limiting.

The LTC1844 regulators are available in a low profile (1mm) SOT-23 (ThinSOTTM) package.

, LTC and LT are registered trademarks of Linear Technology Corporation. VLDO and ThinSOT are trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners.

TYPICAL APPLICATIO

Fixed Voltage Low Noise, VLDO Linear Regulator

VIN 3.3V TO 6.5V

OFF ON

IN

OUT

1?F LTC1844-3.3

SHDN BYP GND

VOUT 3.3V 1?F

0.1?F

1844 TA01

DROPOUT VOLTAGE (mV)

LTC1844-3.3 Dropout Voltage vs Load Current

120

100

80

60

40

20

0 0 25 50 75 100 125 150 IOUT (mA)

1844 TA02

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LTC1844 Series

U WW W

ABSOLUTE AXI U RATI GS (Note 1)

Supply Voltage (IN) ....................................... ? 7V to 7V Input Voltage

SHDN, BYP, ADJ .................................... ? 0.3V to 7V Output Voltage

OUT ........................................................ ? 0.3V to 7V OUT to IN .................................................. ? 7V to 7V

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

Operating Junction Temperature Range (Notes 2, 10) .....................................?40?C to 125?C

Storage Temperature Range ................. ? 65?C to 150?C Lead Temperature (Soldering, 10 sec).................. 300?C

UW U PACKAGE/ORDER I FOR ATIO

TOP VIEW

TOP VIEW

IN 1 GND 2 SHDN 3

5 OUT 4 BYP

IN 1 GND 2 SHDN 3

5 OUT 4 ADJ

S5 PACKAGE 5-LEAD PLASTIC TSOT-23

TJMAX = 125?C, JA = 250?C/ W, JC = 90?C/ W SEE THE APPLICATIONS INFORMATION SECTION

S5 PACKAGE 5-LEAD PLASTIC TSOT-23

TJMAX = 125?C, JA = 250?C/ W, JC = 90?C/ W SEE THE APPLICATIONS INFORMATION SECTION

ORDER PART NUMBER

S5 PART MARKING

ORDER PART NUMBER

LTC1844ES5-1.5 LTC1844ES5-1.8 LTC1844ES5-2.5 LTC1844ES5-2.8 LTC1844ES5-3.3

LTF1 LTF2 LTF3 LTQK LTF4

LTC1844ES5-SD

Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF

Lead Free Part Marking:

S5 PART MARKING

LTE8

Consult LTC Marketing for parts specified with wider operating temperature ranges.

TOP VIEW

IN 1 GND 2 BYP 3

5 OUT 4 ADJ

S5 PACKAGE 5-LEAD PLASTIC TSOT-23

TJMAX = 125?C, JA = 250?C/ W, JC = 90?C/ W SEE THE APPLICATIONS INFORMATION SECTION

ORDER PART NUMBER

LTC1844ES5-BYP

S5 PART MARKING

LTE9

ELECTRICAL CHARACTERISTICS The denotes specifications which apply over the full operating

temperature range, otherwise specifications are at TA = 25?C. VIN = VOUT + 0.5V, unless otherwise noted. (Note 2)

SYMBOL PARAMETER

CONDITIONS

MIN TYP MAX

VIN

Input Voltage

IIN

Quiescent Current

SHDN = VIN

1.6

6.5

35

55

80

IINSHDN VIN Shutdown Supply Current

SHDN = 0V

0.01

1

VOUT% Regulated Output Voltage

LTC1844-3.3 VIN = 3.8V to 6.5V, IOUT = 0mA to 150mA

?1.50

1.50

(Notes 3, 4, 5)

LTC1844-3.3 VIN = 3.8V to 6.5V, IOUT = 0mA to 150mA ?1.75

1.75

LTC1844-2.8 VIN = 3.3V to 6.5V, IOUT = 0mA to 150mA

?1.50

1.50

LTC1844-2.8 VIN = 3.3V to 6.5V, IOUT = 0mA to 150mA ?1.75

1.75

LTC1844-2.5 VIN = 3.0V to 6.5V, IOUT = 0mA to 150mA

?1.50

1.50

LTC1844-2.5 VIN = 3.0V to 6.5V, IOUT = 0mA to 150mA ?1.75

1.75

LTC1844-1.8 VIN = 2.3V to 6.5V, IOUT = 0mA to 150mA

?1.50

1.50

LTC1844-1.8 VIN = 2.3V to 6.5V, IOUT = 0mA to 150mA ?1.75

1.75

2

UNITS

V

?A ?A

?A

%VOUT %VOUT

%VOUT %VOUT

%VOUT %VOUT

%VOUT %VOUT

1844fa

LTC1844 Series

ELECTRICAL CHARACTERISTICS The denotes specifications which apply over the full operating

temperature range, otherwise specifications are at TA = 25?C. VIN = VOUT + 0.5V, unless otherwise noted. (Note 2)

SYMBOL PARAMETER

CONDITIONS

MIN TYP MAX

VADJ

ADJ Pin Voltage (Notes 3, 5)

VLNR Line Regulation (Notes 3, 5)

VLDR Load Regulation (Notes 3, 5) VDO Dropout Voltage (Notes 6, 7)

LTC1844-1.5 VIN = 2.0V to 6.5V, IOUT = 0mA to 150mA

?1.50

1.50

LTC1844-1.5 VIN = 2.2V to 6.5V, IOUT = 0mA to 150mA ?2.00

2.00

LTC1844-1.5 VIN = 2.0V to 6.5V, IOUT = 0mA to 100mA ?2.50

2.00

LTC1844-BYP VIN = 1.75V to 6.5V, IOUT = 0mA to 150mA

?1.50

1.50

LTC1844-BYP VIN = 2.2V to 6.5V, IOUT = 0mA to 150mA ?1.75

1.75

LTC1844-BYP VIN = 1.75V to 6.5V, IOUT = 0mA to 100mA ?3.50

1.75

LTC1844-SD VIN = 1.75V to 6.5V, IOUT = 0mA to 150mA

?1.50

1.50

LTC1844-SD VIN = 2.2V to 6.5V, IOUT = 0mA to 150mA ?1.75

1.75

LTC1844-SD VIN = 1.75V to 6.5V, IOUT = 0mA to 100mA ?3.50

1.75

LTC1844-BYP VIN = 1.75V to 6.5V, IOUT = 0mA to 150mA

1.233 1.25 1.271

LTC1844-BYP VIN = 2.2V to 6.5V, IOUT = 0mA to 150mA 1.230

1.274

LTC1844-BYP VIN = 1.75V to 6.5V, IOUT = 0mA to 100mA 1.208

1.274

LTC1844-SD VIN = 1.75V to 6.5V, IOUT = 0mA to 150mA

1.233 1.25 1.271

LTC1844-SD VIN = 2.2V to 6.5V, IOUT = 0mA to 150mA 1.230

1.274

LTC1844-SD VIN = 1.75V to 6.5V, IOUT = 0mA to 100mA 1.208

1.274

LTC1844-3.3 VIN = 3.4V to 6.5V, IL = 1mA

4

20

LTC1844-2.8 VIN = 2.9V to 6.5V, IL = 1mA

4

20

LTC1844-2.5 VIN = 2.6V to 6.5V, IL = 1mA

4

20

LTC1844-1.8

VIN = 2.2V to 6.5V, IL = 1mA VIN = 1.9V to 6.5V, IL = 1mA VIN = 1.9V to 6.5V, IL = 1mA

4

20

4

20

4

30

LTC1844-1.5

VIN = 2.2V to 6.5V, IL = 1mA VIN = 1.6V to 6.5V, IL = 1mA VIN = 1.6V to 6.5V, IL = 1mA

4

20

4

20

4

80

LTC1844-BYP VIN = 2.2V to 6.5V, IL = 1mA VIN = 1.6V to 6.5V, IL = 1mA VIN = 1.6V to 6.5V, IL = 1mA

4

20

4

20

4

80

LTC1844-SD

VIN = 2.2V to 6.5V, IL = 1mA VIN = 1.6V to 6.5V, IL = 1mA VIN = 1.6V to 6.5V, IL = 1mA

4

20

4

20

4

80

LTC1844-3.3 VIN = 3.8V, IOUT = 0mA to 150mA

9

20

LTC1844-2.8 VIN = 3.3V, IOUT = 0mA to 150mA

9

20

LTC1844-2.5 VIN = 3.0V, IOUT = 0mA to 150mA

9

20

LTC1844-1.8 VIN = 2.3V, IOUT = 0mA to 150mA

9

20

LTC1844-1.5 VIN = 2.2V, IOUT = 0mA to 150mA

VIN = 2.0V, IOUT = 0mA to 100mA

9

20

9

40

LTC1844-BYP VIN = 2.2V, IOUT = 0mA to 150mA

VIN = 1.75V, IOUT = 0mA to 100mA

9

20

9

50

LTC1844-SD VIN = 2.2V, IOUT = 0mA to 150mA

VIN = 1.75V, IOUT = 0mA to 100mA

9

20

9

50

LTC1844-3.3 IOUT = 50mA IOUT = 150mA

30

55

90

150

LTC1844-2.8 IOUT = 50mA IOUT = 150mA

35

60

105

165

LTC1844-2.5 IOUT = 50mA IOUT = 150mA

45

75

135

200

LTC1844-1.8 IOUT = 50mA IOUT = 150mA

85

120

230

300

UNITS

%VOUT %VOUT %VOUT %VOUT %VOUT %VOUT %VOUT %VOUT %VOUT

V V V

V V V

mV

mV

mV

mV mV mV

mV mV mV

mV mV mV

mV mV mV

mV

mV

mV

mV

mV mV

mV mV

mV mV

mV mV

mV mV

mV mV

mV mV

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LTC1844 Series

ELECTRICAL CHARACTERISTICS The denotes specifications which apply over the full operating

temperature range, otherwise specifications are at TA = 25?C. VIN = VOUT + 0.5V, unless otherwise noted. (Note 2)

SYMBOL PARAMETER

CONDITIONS

MIN TYP MAX

LTC1844-1.5 LTC1844-BYP LTC1844-SD

IOUT = 50mA IOUT = 150mA

IOUT = 50mA IOUT = 150mA

IOUT = 50mA IOUT = 150mA

115 160

350 450

45

75

135 200

45

75

135 200

ILIM

Output Current Limit

en

Output Voltage Noise

160

350

f = 10Hz to 100kHz, CBP = 0.1?F, COUT = 10?F, IL = 150mA

60

f = 10Hz to 100kHz, CBP = 0.1?F, COUT = 1?F, IL = 150mA

65

VSHDN tDELAY

SHDN Input Threshold Shutdown Exit Delay

CBP = 0.01?F, COUT = 1?F, No load CBP = 0.01?F, COUT = 1?F, No load

0.35 0.65

0.9

70

100

200

TSHDN Thermal Shutdown Limit

155

TSHDN Thermal Shutdown Hysteresis

10

IADJ

ADJ Pin Bias Current

(Notes 3, 8)

30

100

IIRL

Input Reverse Leakage Current LTC1844-3.3, LTC1844-2.8, LTC1844-2.5, LTC1844-1.8,

LTC1844-1.5, VIN = ?5V, VOUT = 0V

200 500

LTC1844-BYP, LTC1844-SD, VIN = ?5V, VOUT = 0V

1000 1500

IORL

Output Reverse Leakage Current VIN = 0V, VOUT = VOUT(NOMINAL)

(Note 9)

VIN = 0V, VOUT = VOUT(NOMINAL)

0.01 0.1

1.2

VOSH

Start-Up Overshoot

RL = 1k, SHDN Rise Time 1?s

2

VRP

Output Ripple Rejection

(VIN ? VOUT) = 1V (Avg), VRIPPLE = 0.5VP-P,

50

fRIPPLE = 120Hz, ILOAD = 100mA

UNITS mV mV mV mV mV mV mA

?VRMS ?VRMS

V ?s ?s ?C ?C nA ?A

?A ?A ?A %VOUT dB

Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired.

Note 2: The LTC1844 is tested and specified under pulse load conditions such that TJ TA. The LTC1844E is guaranteed to meet performance specifications from 0?C to 70?C. Specifications over the ? 40?C to 125?C operating junction temperature range are assured by design, characterization and correlation with statistical process controls.

Note 3: The LTC1844 adjustable versions are tested and specified for these conditions with the ADJ pin connected to the OUT pin for a VOUT(NOMINAL) of 1.25V. Note 4: Operating conditions are limited by maximum junction temperature. The regulated output voltage specification will not apply for all possible combinations of input voltage and output current. When operating at maximum input voltage, the output current range must be limited. When operating at maximum output current, the input voltage range must be limited.

Note 5: The LTC1844's high precision degrades slightly at high temperatures (TJ > 70?C) with input voltages below 2.2V. The lower output voltage versions have been split into higher and lower accuracy input voltage ranges to reflect this.

Note 6: To ensure adequate input supply voltage, the LTC1844 adjustable versions are tested and specified for these conditions with an external resistor divider (two 100k resistors) for an output voltage of 2.50V. The external resistor divider will add a 5?A load on the output.

Note 7: Dropout voltage is (VIN ? VOUT) when VOUT falls to 100mV below its nominal value measured at VIN = VOUT + 0.5V. For example, the LTC1844-3.3 is tested by measuring the VOUT at VIN = 3.8V, then VIN is lowered until VOUT falls 100mV below the measured value. The difference (VIN ? VOUT) is then measured and defined as VDO. Note 8: ADJ pin bias current flows into the ADJ pin.

Note 9: Output reverse leakage current is tested with the IN pin grounded and the OUT pin forced to the rated output voltage.

Note 10: This IC includes overtemperature protection that is intended to protect the device during momentary overload conditions. Junction temperature will exceed 125?C when overtemperature protection is active. Continuous operation above the specified maximum operating junction temperature may impair device reliability.

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VOUT (V)

UW

TYPICAL PERFOR A CE CHARACTERISTICS

LTC1844 Series

VOUT vs Temperature

1.520 VOUT = 1.5V

1.515

1.510

1.505

1.500

1.495

1.490

1.485

1.480 ? 50 ? 25

0 25 50 75 TEMPERATURE (?C)

100 125

1844 G01

VOUT vs Temperature

2.820 VOUT = 2.8V

2.815

2.810

2.805

2.800

2.795

2.790

2.785

2.780 ? 50 ? 25

0 25 50 75 TEMPERATURE (?C)

100 125

1844 G04

Quiescent Current vs Temperature

70

60

50

40

30

20

10

0 ?50 ?25

0 25 50 75 TEMPERATURE (?C)

100 125

1844 G07

CURRENT LIMIT (mA)

VOUT (V)

VOUT (V)

VOUT vs Temperature

1.820 VOUT = 1.8V

1.815

1.810

1.805

1.800

1.795

1.790

1.785

1.780 ? 50 ? 25

0 25 50 75 TEMPERATURE (?C)

100 125

1844 G02

VOUT vs Temperature

3.320 VOUT = 3.3V

3.315

3.310

3.305

3.300

3.295

3.290

3.285

3.280 ? 50 ? 25

0 25 50 75 TEMPERATURE (?C)

100 125

1844 G05

Current Limit vs Temperature

500 VOUT = 2.8V

450

400

350

300

250

200 ?50 ?25

0 25 50 75 TEMPERATURE (?C)

100 125

1844 G08

SHDN THRESHOLD (mV)

VOUT (V)

VOUT (V)

VOUT vs Temperature

2.520 VOUT = 2.5V

2.515

2.510

2.505

2.500

2.495

2.490

2.485

2.480 ? 50 ? 25

0 25 50 75 TEMPERATURE (?C)

100 125

1844 G03

VOUT vs Temperature

1.270 VOUT = ADJ

1.265

1.260

1.255

1.250

1.245

1.240

1.235

1.230 ? 50 ? 25

0 25 50 75 TEMPERATURE (?C)

100 125

1844 G05

SHDN Threshold vs Temperature

800 ILOAD = 1mA

750

700

650

600

550

500

450

400 ? 50 ? 25

0 25 50 75 TEMPERATURE (?C)

100 125

1844 G09

IQ (?A)

VOUT (V)

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