1/14March 2005
INPUT VOLTAGE FROM 2.5V T O 6V
STABLE WITH LOW ESR CERA M IC
CAPACITORS
U LTRA LOW DROPOUT VOLTAG E (100mV
TY P. AT 150mA LOA D, 0.4m V TYP. AT 1mA
LOAD)
VERY LOW QUIESCENT CURRENT (85µ A
TY P. AT NO LO AD, 170µ A TYP. AT 150m A
LOAD; MA X 1.5 µA IN OFF MO D E)
GUARANTEED OUTPUT CURRENT UP TO
150mA
WIDE RANGE OF OUTPUT VOLTAGE: 1.2V;
1.22 V; 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-O N TIME: TYP. 200µs [CO=1µF,
CBYP= 10nF AND IO=1mA]
LOGIC-CONTROLLED ELECTRONIC
SHUTDOWN
INTERNAL CURRENT AND THERMAL LIMIT
OUTPUT LOW NOISE VOLTAGE 30µ VRMS
OV ER 10Hz to 100KHz
S.V.R. OF 60dB AT 1KHz, 50dB AT 10KHz
TEMPERATURE RANGE: -40°C TO 125°C
DESCRIPTION
The LD3 985 provides up to 150mA, from 2.5V to
6V inpu t 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 th e batt ery life. Power
supply rejection is better than 60 dB at low
frequencies and starts to roll off at 10KHz. High
power s upply rejection is maintained do wn to l ow
input voltage levels common to battery operated
circuits. Shutdown Logic Control function is
avai lable, this m eans t hat when the device is used
as local regulator, it is possibl e 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 po wered wireless systems.
LD3985
SERIES
ULTRA LOW DROP-LOW NOISE BICMOS VOLTAGE
REGULATORS LOW ESR CAPAC IT ORS COMPATIBLE
Fi gure 1 : Schematic Diagr am
Flip-Chip
(1.57x1.22) TSOT23-5LSOT23-5L
Rev. 9
LD3985 SERIES
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Table 1: Absolute Maximum Rati ngs
Absolute Maximum Ratings are those values beyond which damage to the dev ice may occur. Functional operation under these condition is
not implie d.
(* ) T he inpu t pin i s able to withstand non repetitive spike of 6.5V for 2 00m s.
Table 2: Therm al Data
Table 3: Order Codes
(* ) A vailable on re quest.
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
SOT23-5L TSOT23-5L Flip-Chip OUTPUT VOLTAGES
LD3985M12R (*) LD3985G12R (*) LD3985J12R (*) 1.20 V
LD3985M122R LD3985G122R (*) LD3985J122R 1.22 V
LD3985M125R (*) LD3985G125R (*) LD3985J125R 1.25 V
LD3985M135R (*) LD3985G135R (*) LD3985J135R 1.35 V
LD3985M15R LD3985G15R (*) LD3985J15R (*) 1.5 V
LD3985M18R LD3985G18R LD3985J18R 1.8 V
LD3985M20R (*) LD3985G20R (*) LD3985J20R (*) 2.0 V
LD3985M21R (*) LD3985G21R (*) LD3985J21R (*) 2.1 V
LD3985M22R (*) LD3985G22R (*) LD3985J22R (*) 2.2 V
LD3985M24R (*) LD3985G24R (*) LD3985J24R 2.4 V
LD3985M25R LD3985G25R LD3985J25R 2.5 V
LD3985M26R (*) LD3985G26R (*) LD3985J26R 2.6 V
LD3985M27R LD3985G27R LD3985J27R 2.7 V
LD3985M28R (*) LD3985G28R (*) LD3985J28R 2.8 V
LD3985M285R (*) LD3985G285R (*) LD3985J285R (*) 2.85 V
LD3985M29R LD3985G29R LD3985J29R 2.9 V
LD3985M30R (*) LD3985G30R (*) LD3985J30R 3.0 V
LD3985M31R (*) LD3985G31R (*) LD3985J31R 3.1 V
LD3985M32R (*) LD3985G32R (*) LD3985J32R (*) 3.2 V
LD3985M33R LD3985G33R (*) LD3985J33R 3.3 V
LD3985M44R (*) LD3985G44R (*) LD3985J44R (*) 4.4 V
LD3985M47R LD3985G47R (*) LD3985J47R 4.7 V
LD3985M48R (*) LD3985G48R (*) LD3985J48R 4.8 V
LD3985M49R (*) LD3985G49R (*) LD3985J49R (*) 4.9 V
LD3985M50R (*) LD3985G50R (*) LD3985J50R (*) 5.0 V
LD3985 SERIES
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Fi gure 2 : Connectio n Diagr am (top view for SOT and TSOT, top through view for Flip-Chip)
Table 4: Pin Descrip tion
Fi gure 3 : Ty pical A ppl icati on Circuit
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 V oltage: ON MODE when VINH 1.2V, OFF MODE when VINH
0.4V (Do not leave floating, not internally pulled down/up)
4 5 BYP ASS 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 5: Electrical Characteristics For LD3985 (Tj = 25°C, VI = VO(NOM) +0.5V, CI = 1µF,
CBYP = 10nF, IO = 1mA, VINH = 1.4V, unless otherwise speci fied)
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 = 1 mA -2 2 % of
VO(NOM)
TJ= -40 to 125°C -3 3
VOLine Regulation (Note 1) VI = VO(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 = VO(NOM) + 1 V, IO = 150mA,
tR= tF = 30µs 1.5 mVPP
IQQuiescent Current
ON MODE: VINH = 1.2V IO = 0 85 µA
IO = 0 TJ= -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 TJ= -40 to 125°C 2
IO = 50mA 20
IO = 50mA TJ= -40 to 125°C 35
IO = 100mA 45
IO = 100mA TJ= -40 to 125°C 70
IO = 150mA 60
IO = 150mA TJ= -40 to 125°C 100
ISC Short Circuit Current RL = 0 600 m A
SVR Supply Voltage Rejection VI = VO(NOM)+0.25V ±
VRIPPLE = 0.1V, IO= 50mA
VO(NOM) < 2.5V, VI = 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 = 2.5V to 6V TJ= -40 to
125°C 0.4 V
Inhibit Input Logic High 1.2
IINH Inhibit Input Current VINH = 0.4V VI = 6V ±1 nA
eN Output Noise Voltage BW = 10 Hz to 100 KHz CO = 1 µF30µVRMS
tON Turn On Time (Note 4) CBYP = 10 nF 100 250 µs
TSHDN Thermal Shutdown Note 5 160 °C
LD3985 SERIES
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Note 1 – For VO(NOM) < 2V, VI = 2. 5V
Note 2 – For VO(NOM) = 1.25V, V I = 2.5V
Note 3 – Drop out volt age is th e i nput-to -output vo l tage diff erence at which the output voltage i s 100m V below its n om i nal valu e. This spe ci-
fication does not apply for input volt ages below 2.5V .
Note 4 – Turn-on time is time measured between the enable input just exceeding VINH Hi gh Value and the output v oltage just reaching 95%
of its nomi nal v al ue
Note 5 – Typical thermal protection hyst eresis is 20°C
Note 6 - The minimum c apacitor value is 1µF, anyway the LD3985 is still st ab le if the compensation c apacitor has a 30% tolerance in all
temperature range.
TYPICAL PERF ORMANCE CHARACTERISTICS (Tj = 25°C, VI = VO(NOM) +0.5V, CI = CO = 1µF,
CBYP = 10nF, IO = 1mA , VINH = 1.4V, unless otherwise sp ecified)
Fi gure 4 : Output Voltage vs Temperature
Fi gure 5 : Output Voltage vs Temperature
Fi gure 6 : Output Voltage vs Temperature
Fi gure 7 : Shut down Vo ltage vs Temperature
COOutput Capacitor Capacitance (Note 6) 1 22 µF
ESR 5 5000 m
Symbol Parameter Test Conditions Min. Typ. Max. Unit
LD3985 SERIES
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Fi gure 8 : Shut down Vo ltage vs Temperature
Fi gure 9 : Line Regulation vs Temperature
Fi gure 1 0: Line Regulation vs Tem perature
Fi gure 1 1: Line Regulation vs Tem perature
Fi gure 1 2: Load Regulation vs Temperature
Fi gure 1 3: Load Regulation vs Temperature
LD3985 SERIES
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Fi gure 1 4: Load Regulation vs Temperature
Fi gure 1 5: Quiescent Current vs Temperature
Fi gure 1 6: Quiescent Current vs Temperature
Fi gure 1 7: Quiescent Current vs Temperature
Fi gure 1 8: Supply Voltage Rejection vs
Frequency
Fi gure 1 9: Load Transient Response
VI = 3.2V, IO = 1 to 150 m A , Rise-Fal l tim e = 1µsec
LD3985 SERIES
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Fi gure 2 0: Line Transient Response
Fi gure 2 1: START-UP
Fi gure 2 2: TURN-OFF
VI = 3.8V to 4.4V, TJ = 25 °C, IO = 150mA, CI = CO = 1µF (X 7R),
CBYP = 10nF, Rise-Fall time = 1µsec, VO = 2.7V
VI = 3.3V , IO = 1mA, CI = CO = 1µF (cer), CBYP = 10nF, Tr = 20ns,
VO = 2. 8V
VI = 3.3V, IO = 1mA, CI = CO = 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
7282780B
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 Revisio n Descrip tion of Change s
07-May-2004 6 Part Number Status Changed on Table 3.
05-Oct-2004 7 tON values are Changed on Table 5.
27-Oct-2004 8 Order Codes changed - Table 3.
17-Mar-2005 9 Improved Drawing Quality for Figures 19-20-21-22.
LD3985 SERIES
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