LD3985G125 - STMicroelectronics, Inc.

1/14May 2004

■INPUT VOLTAGE FROM 2.5V TO 6V

■STABLE WITH LOW ESR CERAMIC

CAPACITORS

■ULTRA LOW DROPOUT VOLTAGE (100mV

TYP. AT 150mA LOAD, 0.4mV TYP. AT 1mA

LOAD)

■VERY LOW QUIESCENT CURRENT (85µA

TYP. AT NO LOAD, 170µA TYP. AT 150mA

LOAD; MAX 1.5µA IN OFF MODE)

■GUARANTEED OUTPUT CURRENT UP TO

150mA

■WIDE RANGE OF OUTPUT VOLTAGE: 1.2V;

1.22V; 1.25V; 1.35V; 1.5V; 1.8V; 2V; 2.1V;

2.2V; 2.4V; 2.5V; 2.6V; 2.7V; 2.8V; 2.85V;

2.9V; 3V; 3.1V; 3.2V; 3.3V; 4.7V; 5V

■FAST TURN-ON TIME: TYP. 200µs [CO=1µF,

CBYP= 10nF AND IO=1mA]

■LOGIC-CONTROLLED ELECTRONIC

SHUTDOWN

■INTERNAL CURRENT AND THERMAL LIMIT

■OUTPUT LOW NOISE VOLTAGE 30µVRMS

OVER 10Hz to 100KHz

■S.V.R. OF 60dB AT 1KHz, 50dB AT 10KHz

■TEMPERATURE RANGE: -40°C TO 125°C

DESCRIPTION

The LD3985 provides up to 150mA, from 2.5V to

6V input voltage.

The ultra low drop-voltage, low quiescent current

and low noise make it suitable for low power

applications and in battery powered systems.

Regulator ground current increases only slightly in

dropout, further prolonging the battery life. Power

supply rejection is better than 60 dB at low

frequencies and starts to roll off at 10KHz. High

power supply rejection is maintained down to low

input voltage levels common to battery operated

circuits. Shutdown Logic Control function is

available, this means that when the device is used

as local regulator, it is possible to put a part of the

board in standby, decreasing the total power

consumption. The LD3985 is designed to work

with low ESR ceramic capacitors. Typical

applications are in mobile phone and similar

battery powered wireless systems.

LD3985

SERIES

ULTRA LOW DROP-LOW NOISE BICMOS VOLTAGE

REGULATORS LOW ESR CAPACITORS COMPATIBLE

SCHEMATIC DIAGRAM

Flip-Chip

(1.57x1.22) TSOT23-5LSOT23-5L

Rev. 7

LD3985 SERIES

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Table 1: Absolute Maximum Ratings

Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is

not implied.

(*) The input pin is able to withstand non repetitive spike of 6.5V for 200ms.

Table 2: Thermal Data

Figure 1: Connection Diagram (top view for SOT and TSOT, top through view for Flip-Chip)

Table 3: Pin Description

Symbol Parameter Value Unit

VIDC Input Voltage -0.3 to 6 (*) V

VODC Output Voltage -0.3 to VI+0.3 V

VINH INHIBIT Input Voltage -0.3 to VI+0.3 V

IOOutput Current Internally limited

PDPower Dissipation Internally limited

TSTG Storage Temperature Range -65 to 150 °C

TOP Operating Junction Temperature Range -40 to 125 °C

Symbol Parameter SOT23-5L/

TSOT23-5L Flip-Chip Unit

Rthj-case Thermal Resistance Junction-case 81 °C/W

Rthj-amb Thermal Resistance Junction-ambient 255 170 °C/W

Pin N°

SOT23-5L/

TSOT23-5L

Pin N°

Flip-Chip Symbol Name and Function

14V

IInput Voltage of the LDO

2 2 GND Common Ground

31V

INH Inhibit Input Voltage: ON MODE when VINH ≥ 1.2V, OFF MODE when VINH ≤

0.4V (Do not leave floating, not internally pulled down/up)

4 5 BYPASS Bypass Pin: Connect an external capacitor (usually 10nF) to minimize noise

voltage

53V

OOutput Voltage of the LDO

TSOT23-5L/SOT23-5L Flip-Chip

LD3985 SERIES

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Table 4: Ordering Codes

(*) Available on request.

Figure 2: Typical Application Circuit

SOT23-5L TSOT23-5L Flip-Chip OUTPUT VOLTAGES

LD3985M12 (*) LD3985G12 (*) LD3985J12 (*) 1.20 V

LD3985M122 LD3985G122 (*) LD3985J122 1.22 V

LD3985M125 (*) LD3985G125 (*) LD3985J125 1.25 V

LD3985M135 (*) LD3985G135 (*) LD3985J135 1.35 V

LD3985M15 LD3985G15 (*) LD3985J15 (*) 1.5 V

LD3985M18 LD3985G18 LD3985J18 1.8 V

LD3985M20 (*) LD3985G20 (*) LD3985J20 (*) 2.0 V

LD3985M21 (*) LD3985G21 (*) LD3985J21 (*) 2.1 V

LD3985M22 (*) LD3985G22 (*) LD3985J22 (*) 2.2 V

LD3985M24 (*) LD3985G24 (*) LD3985J24 2.4 V

LD3985M25 LD3985G25 LD3985J25 2.5 V

LD3985M26 (*) LD3985G26 (*) LD3985J26 2.6 V

LD3985M27 LD3985G27 LD3985J27 2.7 V

LD3985M28 (*) LD3985G28 (*) LD3985J28 2.8 V

LD3985M285 (*) LD3985G285 (*) LD3985J285 (*) 2.85 V

LD3985M29 LD3985G29 LD3985J29 2.9 V

LD3985M30 (*) LD3985G30 (*) LD3985J30 3.0 V

LD3985M31 (*) LD3985G31 (*) LD3985J31 3.1 V

LD3985M32 (*) LD3985G32 (*) LD3985J32 (*) 3.2 V

LD3985M33 LD3985G33 (*) LD3985J33 3.3 V

LD3985M44 (*) LD3985G44 (*) LD3985J44 (*) 4.4 V

LD3985M47 LD3985G47 (*) LD3985J47 4.7 V

LD3985M48 (*) LD3985G48 (*) LD3985J48 4.8 V

LD3985M49 (*) LD3985G49 (*) LD3985J49 (*) 4.9 V

LD3985M50 (*) LD3985G50 (*) LD3985J50 (*) 5.0 V

LD3985 SERIES

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Table 5: Electrical Characteristics For LD3985 (Tj= 25°C, VI=V

O(NOM) +0.5V, CI=1µF,

CBYP = 10nF, IO=1mA,V

INH = 1.4V, unless otherwise specified)

Symbol Parameter Test Conditions Min. Typ. Max. Unit

VIOperating Input Voltage 2.5 6 V

VOOutput Voltage < 2.5V IO= 1 mA -50 50 mV

TJ= -40 to 125°C -75 75

VOOutput Voltage ≥2.5V IO=1mA -2 2 %of

VO(NOM)

TJ= -40 to 125°C -3 3

∆VOLine Regulation (Note 1) VI=V

O(NOM) + 0.5 to 6 VTJ= -40 to 125°C -0.1 0.1 %/V

VO= 4.7 to 5V -0.19 0.19

∆VOLoad Regulation IO= 1 mA to 150mA VO<2.5V

TJ= -40 to 125°C 0.002 0.008 %/mA

∆VOLoad Regulation IO= 1 mA to 150mA VO≥2.5V

TJ= -40 to 125°C (for Flip-Chip) 0.0004 0.002 %/mA

IO= 1 mA to 150mA, TJ= -40 to 125°C

(for SOT23-5L/TSOT23-5L), VO≥2.5V 0.0025 0.005

∆VOOutput AC Line Regulation VI=V

O(NOM) +1V,I

O=150mA,

tR=t

F= 30µs 1.5 mVPP

IQQuiescent Current

ON MODE: VINH =1.2V IO=0 85 µA

IO=0 T

J= -40 to 125°C 150

IO= 0 to 150mA 170

IO= 0 to 150mA TJ= -40 to 125°C 250

OFF MODE: VINH = 0.4V 0.003

TJ= -40 to 125°C 1.5

VDROP Dropout Voltage (NOTE 1) IO=1mA 0.4 mV

IO=1mA T

J= -40 to 125°C 2

IO=50mA 20

IO=50mA T

J= -40 to 125°C 35

IO=100mA 45

IO=100mA T

J= -40 to 125°C 70

IO=150mA 60

IO=150mA T

J= -40 to 125°C 100

ISC Short Circuit Current RL= 0 600 mA

SVR Supply Voltage Rejection VI=V

O(NOM)+0.25V ±

VRIPPLE =0.1V, I

O= 50mA

VO(NOM) <2.5V, V

I=2.55V

f=1KHz 60 dB

f=10KHz 50

IO(PK) Peak Output Current VO≥VO(NOM) - 5% 300 550 mA

VINH Inhibit Input Logic Low VI=2.5Vto6V T

J=-40to

125°C 0.4 V

Inhibit Input Logic High 1.2

IINH Inhibit Input Current VINH =0.4V V

I=6V ±1 nA

eN Output Noise Voltage BW=10Hzto100KHz C

O=1µF30µVRMS

tON Turn On Time (Note 4) CBYP = 10 nF 200 µs

TSHDN Thermal Shutdown Note 5 160 °C

LD3985 SERIES

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Note1–ForV

O(NOM) <2V,V

I=2.5V

Note2–ForV

O(NOM) =1.25V,V

I=2.5V

Note3–Dropoutvoltageistheinput-to-outputvoltagedifferenceatwhichtheoutputvoltageis100mVbelowitsnominalvalue.Thisspeci-

fication does not apply for input voltages below 2.5V.

Note 4 – Turn-on time is time measured between the enable input just exceeding VINH High Value and the output voltage just reaching 95%

of its nominal value

Note5–Typicalthermalprotectionhysteresisis20°C

Note 6 - The minimum capacitor value is 1µF, anyway the LD3985 is still stable if the compensation capacitor has a 30% tolerance in all

temperature range.

TYPICAL PERFORMANCE CHARACTERISTICS (Tj= 25°C, VI=V

O(NOM) +0.5V, CI=C

O=1µF,

CBYP =10nF, IO=1mA,V

INH = 1.4V, unless otherwise specified)

Figure 3: Output Voltage vs Temperature

Figure 4: Output Voltage vs Temperature

Figure 5: Output Voltage vs Temperature

Figure 6: Shutdown Voltage vs Temperature

COOutput Capacitor Capacitance (Note 6) 1 22 µF

ESR 5 5000 mΩ

Symbol Parameter Test Conditions Min. Typ. Max. Unit

LD3985 SERIES

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Figure 7: Shutdown Voltage vs Temperature

Figure 8: Line Regulation vs Temperature

Figure 9: Line Regulation vs Temperature

Figure 10: Line Regulation vs Temperature

Figure 11: Load Regulation vs Temperature

Figure 12: Load Regulation vs Temperature

LD3985 SERIES

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Figure 13: Load Regulation vs Temperature

Figure 14: Quiescent Current vs Temperature

Figure 15: Quiescent Current vs Temperature

Figure 16: Quiescent Current vs Temperature

Figure 17: Supply Voltage Rejection vs

Frequency

Figure 18: Load Transient Response

VI=3.2V,I

O= 1 to 150mA, Rise-Fall time = 1µsec

LD3985 SERIES

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Figure 19: Line Transient Response

Figure 20: START-UP

Figure 21: TURN-OFF

VI=3.8Vto4.4V,T

J=25°C,I

O= 150mA, CI=C

O=1µF(X7R),

CBYP = 10nF, Rise-Fall time= 1µsec, VO=2.7V

VI=3.3V,I

O=1mA,C

I=C

O=1µF (cer), CBYP = 10nF, Tr= 20ns,

VO=2.8V

VI=3.3V,I

O=1mA,C

I=C

O=1µF (cer), CBYP = 10nF, Tf=20ns,

VO=2.8V

LD3985 SERIES

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DIM. mm. mils

MIN. TYP MAX. MIN. TYP. MAX.

A 0.90 1.45 35.4 57.1

A1 0.00 0.10 0.0 3.9

A2 0.90 1.30 35.4 51.2

b 0.35 0.50 13.7 19.7

C 0.09 0.20 3.5 7.8

D 2.80 3.00 110.2 118.1

E 1.50 1.75 59.0 68.8

e0.95 37.4

H 2.60 3.00 102.3 118.1

L 0.10 0.60 3.9 23.6

SOT23-5L MECHANICA L DATA

7049676C

LD3985 SERIES

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DIM. mm. mils

MIN. TYP MAX. MIN. TYP. MAX.

A 1.1 43.3

A1 0 0.1 3.9

A2 0.7 1.0 27.6 39.4

b 0.3 0.5 11.8 19.7

C 0.08 0.2 3.1 7.9

D 2.9 114.2

E 2.8 110.2

E1 1.6 63.0

e0.95 37.4

e1 1.9 74.8

L 0.3 0.6 11.8 23.6

TSOT23-5L MECHANICAL DATA

7282780/A

LD3985 SERIES

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DIM. mm. mils

MIN. TYP MAX. MIN. TYP. MAX.

A 0.835 0.9 0.965 32.874 35.433 37.992

A1 0.21 0.25 0.29 8.268 9.843 11.417

A2 0.625 0.65 0.675 24.606 25.591 26.575

b 0.265 0.315 0.365 10.433 12.402 14.370

D 1.510 1.540 1.570 59.449 60.630 61.811

E 1.16 1.19 1.22 45.669 46.850 48.031

e 0.45 0.5 0.55 17.717 19.685 21.654

e1 0.816 0.866 0.916 32.126 34.094 36.063

f 0.345 13.583

f1 0.337 13.268

Flip-Chip5 MECHANICAL DATA

LD3985 SERIES

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DIM. mm. inch

MIN. TYP MAX. MIN. TYP. MAX.

A 180 7.086

C 12.8 13.0 13.2 0.504 0.512 0.519

D 20.2 0.795

N 60 2.362

T 14.4 0.567

Ao 3.13 3.23 3.33 0.123 0.127 0.131

Bo 3.07 3.17 3.27 0.120 0.124 0.128

Ko 1.27 1.37 1.47 0.050 0.054 0.0.58

Po 3.9 4.0 4.1 0.153 0.157 0.161

P 3.9 4.0 4.1 0.153 0.157 0.161

Tape & Reel SOT23-xL MECHANICAL DATA

LD3985 SERIES

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Table 6: Revision History

Date Revision Description of Changes

07-May-2004 7 Part Number Status Changed on Table 4 - Page 3.

LD3985 SERIES

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