TI LP2985A

SLVS522C − JULY 2004 − REVISED OCTOBER 2004
D Available in the Texas Instruments
D
D
D
D
D
D
NanoStar and NanoFree Wafer Chip
Scale Packages
Output Tolerance of:
− 1% (A Grade)
− 1.5% (Standard Grade)
Ultra-Low Dropout, Typically
− 280 mV at Full Load of 150 mA
− 7 mV at 1 mA
Wide VIN Range . . . 16 V Max
Low IQ . . . 850 µA at Full Load at 150 mA
Shutdown Current . . . 0.01 µA Typ
Low Noise . . . 30 µVRMS With 10-nF Bypass
Capacitor
DBV (SOT-23) PACKAGE
(TOP VIEW)
VIN
GND
ON/OFF
1
D
D
D
D
Ceramic
Over-Current and Thermal Protection
High Peak-Current Capability
For VOUT Options 32.3 V, See LP2985LV
Data Sheet
Portable Applications
− Cellular Phones
− Palmtop and Laptop Computers
− Personal Digital Assistants (PDAs)
− Digital Cameras and Camcorders
− CD Players
− MP3 Players
YEQ, YEU, YZQ, OR YZU (WCSP) PACKAGE
(TOP VIEW)
5
VOUT
4
BYPASS
2
3
D Stable With Low-ESR Capacitors, Including
VIN
C3 C1
B2
ON/OFF
VOUT
BYPASS
A3
A1
GND
description/ordering information
The LP2985 family of fixed-output, low-dropout regulators offers exceptional, cost-effective performance for
both portable and nonportable applications. Available in voltages of 2.5 V, 2.6 V, 2.7 V, 2.8 V, 2.85 V, 3 V,
3.1 V, 3.2 V, 3.3 V, and 5 V, the family has an output tolerance of 1% for the A version (1.5% for the non-A version)
and is capable of delivering 150-mA continuous load current. Standard regulator features, such as over-current
and over-temperature protection, are included.
The LP2985 has a host of features that makes the regulator an ideal candidate for a variety of portable
applications:
•
•
•
•
•
Low dropout: A PNP pass element allows a typical dropout of 280 mV at 150-mA load current and 7 mV
at 1-mA load.
Low quiescent current: The use of a vertical PNP process allows for quiescent currents that are
considerably lower than those associated with traditional lateral PNP regulators.
Shutdown: A shutdown feature is available, allowing the regulator to consume only 0.01 µA when the
ON/OFF pin is pulled low.
Low-ESR-capacitor friendly: The regulator is stable with low-ESR capacitors, allowing the use of small,
inexpensive, ceramic capacitors in cost-sensitive applications.
Low noise: A BYPASS pin allows for low-noise operation, with a typical output noise of 30 µV (RMS),
with the use of a 10-nF bypass capacitor.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
NanoStar and NanoFree are trademarks of Texas Instruments.
Copyright  2004, Texas Instruments Incorporated
! " #$%! " &$'(#! )!%*
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!%"!/ (( &
%!%"*
POST OFFICE BOX 655303
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1
SLVS522C − JULY 2004 − REVISED OCTOBER 2004
description/ordering information (continued)
•
Small packaging: For the most space-constraint needs, the regulator is available in SOT-23 package,
as well as NanoStar wafer chip scale packaging, offering an even smaller size with improved thermal
and electrical characteristics. NanoStar package technology is a major breakthrough in IC packaging
concepts, using the die as the package.
ORDERING INFORMATION
TJ
PART
GRADE
VOUT
(NOM)
PACKAGE†
2.5 V
2.6 V
2.7 V
2.8 V
2.85 V
−40°C to 125°C
A grade:
1% tolerance
SOT23-5 (DBV)
3V
3.1 V
3.2 V
3.3 V
5V
ORDERABLE
PART NUMBER
TOP-SIDE
MARKING‡
Reel of 3000
LP2985A-25DBVR
Reel of 250
LP2985A-25DBVT
Reel of 3000
LP2985A-26DBVR
Reel of 250
LP2985A-26DBVT
Reel of 3000
LP2985A-27DBVR
Reel of 250
LP2985A-27DBVT
Reel of 3000
LP2985A-28DBVR
Reel of 250
LP2985A-28DBVT
Reel of 3000
LP2985A-285DBVR
Reel of 250
LP2985A-285DBVT
PREVIEW
Reel of 3000
LP2985A-30DBVR
PREVIEW
Reel of 250
LP2985A-30DBVT
Reel of 3000
LP2985A-31DBVR
Reel of 250
LP2985A-31DBVT
Reel of 3000
LP2985A-32DBVR
Reel of 250
LP2985A-32DBVT
Reel of 3000
LP2985A-33DBVR
Reel of 250
LP2985A-33DBVT
Reel of 3000
LP2985A-50DBVR
Reel of 250
LP2985A-50DBVT
PREVIEW
PREVIEW
PREVIEW
LPJ_
PREVIEW
PREVIEW
LPK_
PREVIEW
† Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at
www.ti.com/sc/package.
‡ DBV: The actual top-side marking has one additional character that designates the assembly/test site.
2
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SLVS522C − JULY 2004 − REVISED OCTOBER 2004
ORDERING INFORMATION (continued)
TJ
PART
GRADE
VOUT
(NOM)
PACKAGE†
2.5 V
LP2985A-25YEQR
2.6 V
LP2985A-26YEQR
2.7 V
LP2985A-27YEQR
2.8 V
LP2985A-28YEQR
2.85 V
3V
NanoStar − WCSP
NanoStar
0.17-mm Bump (YEQ)
LP2985A-31YEQR
3.2 V
LP2985A-32YEQR
3.3 V
LP2985A-33YEQR
5V
LP2985A-50YEQR
2.5 V
LP2985A-25YZQR
2.6 V
LP2985A-26YZQR
2.7 V
LP2985A-27YZQR
3V
A grade:
1% tolerance
LP2985A-30YEQR
3.1 V
2.85 V
LP2985A-28YZQR
NanoFree − WCSP
NanoFree
0.17-mm Bump
(YZQ, Pb-free)
LP2985A-285YZQR
Reel of 3000
LP2985A-30YZQR
3.1 V
LP2985A-31YZQR
3.2 V
LP2985A-32YZQR
3.3 V
LP2985A-33YZQR
5V
LP2985A-50YZQR
2.5 V
LP2985A-25YEUR
2.6 V
LP2985A-26YEUR
2.7 V
LP2985A-27YEUR
2.8 V
LP2985A-28YEUR
2.85 V
3V
NanoFree − WCSP
NanoFree
0.30-mm Bump (YEU)
LP2985A-285YEUR
Reel of 3000
LP2985A-30YEUR
3.1 V
LP2985A-31YEUR
3.2 V
LP2985A-32YEUR
3.3 V
LP2985A-33YEUR
5V
LP2985A-50YEUR
2.5 V
LP2985A-25YZUR
2.6 V
LP2985A-26YZUR
2.7 V
LP2985A-27YZUR
2.8 V
2.85 V
3V
TOP-SIDE
MARKING‡
LP2985A-285YEQR
Reel of 3000
2.8 V
−40°C to 125°C
ORDERABLE
PART NUMBER
LP2985A-28YZUR
NanoFree − WCSP
NanoFree
0.30-mm Bump
(YZU, Pb-free)
LP2985A-285YZUR
Reel of 3000
LP2985A-30YZUR
3.1 V
LP2985A-31YZUR
3.2 V
LP2985A-32YZUR
3.3 V
LP2985A-33YZUR
5V
LP2985A-50YZUR
† Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at
www.ti.com/sc/package.
‡ YEQ/YZQ, YEU/YZU: The actual top-side marking has three preceding characters to denote year, month, and sequence code, and one
following character to designate the assembly/test site. Pin 1 identifier indicates solder-bump composition (1 = SnPb, • = Pb-free).
POST OFFICE BOX 655303
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SLVS522C − JULY 2004 − REVISED OCTOBER 2004
ORDERING INFORMATION (continued)
TJ
PART GRADE
VOUT
(NOM)
PACKAGE†
2.5 V
2.6 V
2.7 V
2.8 V
2.85 V
−40°C to 125°C
Standard grade:
1.5% tolerance
SOT-23 (DBV)
3V
3.1 V
3.2 V
3.3 V
5V
ORDERABLE
PART NUMBER
TOP-SIDE
MARKING‡
Reel of 3000
LP2985-25DBVR
Reel of 250
LP2985-25DBVT
Reel of 3000
LP2985-26DBVR
Reel of 250
LP2985-26DBVT
Reel of 3000
LP2985-27DBVR
Reel of 250
LP2985-27DBVT
Reel of 3000
LP2985-28DBVR
Reel of 250
LP2985-28DBVT
Reel of 3000
LP2985-285DBVR
Reel of 250
LP2985-285DBVT
PREVIEW
Reel of 3000
LP2985-30DBVR
PREVIEW
Reel of 250
LP2985-30DBVT
Reel of 3000
LP2985-31DBVR
Reel of 250
LP2985-31DBVT
Reel of 3000
LP2985-32DBVR
Reel of 250
LP2985-32DBVT
Reel of 3000
LP2985-33DBVR
Reel of 250
LP2985-33DBVT
Reel of 3000
LP2985-50DBVR
Reel of 250
LP2985-50DBVT
PREVIEW
PREVIEW
PREVIEW
LPG_
PREVIEW
PREVIEW
LPF_
PREVIEW
† Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at
www.ti.com/sc/package.
‡ DBV: The actual top-side marking has one additional character that designates the assembly/test site.
4
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SLVS522C − JULY 2004 − REVISED OCTOBER 2004
ORDERING INFORMATION (continued)
TJ
PART GRADE
VOUT
(NOM)
PACKAGE†
2.5 V
LP2985-25YEQR
2.6 V
LP2985-26YEQR
2.7 V
LP2985-27YEQR
2.8 V
LP2985-28YEQR
2.85 V
3V
NanoStar − WCSP
NanoStar
0.17-mm Bump (YEQ)
LP2985-31YEQR
3.2 V
LP2985-32YEQR
3.3 V
LP2985-33YEQR
5V
LP2985-50YEQR
2.5 V
LP2985-25YZQR
2.6 V
LP2985-26YZQR
2.7 V
LP2985-27YZQR
3V
Standard grade:
1.5% tolerance
LP2985-30YEQR
3.1 V
2.85 V
LP2985-28YZQR
NanoFree − WCSP
NanoFree
0.17-mm Bump
(YZQ, Pb-free)
LP2985-285YZQR
Reel of 3000
LP2985-30YZQR
3.1 V
LP2985-31YZQR
3.2 V
LP2985-32YZQR
3.3 V
LP2985-33YZQR
5V
LP2985-50YZQR
2.5 V
LP2985-25YEUR
2.6 V
LP2985-26YEUR
2.7 V
LP2985-27YEUR
2.8 V
LP2985-28YEUR
2.85 V
3V
NanoStar − WCSP
NanoStar
0.30-mm Bump (YEU)
LP2985-285YEUR
Reel of 3000
LP2985-30YEUR
3.1 V
LP2985-31YEUR
3.2 V
LP2985-32YEUR
3.3 V
LP2985-33YEUR
5V
LP2985-50YEUR
2.5 V
LP2985-25YZUR
2.6 V
LP2985-26YZUR
2.7 V
LP2985-27YZUR
2.8 V
2.85 V
3V
TOP-SIDE
MARKING‡
LP2985-285YEQR
Reel of 3000
2.8 V
−40°C to 125°C
ORDERABLE
PART NUMBER
LP2985-28YZUR
NanoFree − WCSP
NanoFree
0.30-mm Bump
(YZU, Pb-free)
Reel of 3000
LP2985-285YZUR
LP2985-30YZUR
3.1 V
LP2985-31YZUR
3.2 V
LP2985-32YZUR
3.3 V
LP2985-33YZUR
5V
LP2985-50YZUR
† Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at
www.ti.com/sc/package.
‡ YEQ/YZQ, YEU/YZU: The actual top-side marking has three preceding characters to denote year, month, and sequence code, and one
following character to designate the assembly/test site. Pin 1 identifier indicates solder-bump composition (1 = SnPb, • = Pb-free).
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5
SLVS522C − JULY 2004 − REVISED OCTOBER 2004
functional block diagram
VIN
ON/OFF
1.23 V
VREF
−
+
BYPASS
VOUT
Over-Current/
Over-Temperature
Protection
basic application circuit
LP2985A-xxDBVR
VIN
1
VOUT
5
2.2 µF†
1 µF†
GND
2
ON/OFF‡
3
4
BYPASS
10 nF§
† Minimum COUT value for stability (can be increased without limit for improved stability and transient response)
‡ ON/OFF must be actively terminated. Connect to VIN if shutdown feature is not used.
§ Optional BYPASS capacitor for low-noise operation
6
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SLVS522C − JULY 2004 − REVISED OCTOBER 2004
absolute maximum ratings over the virtual junction temperature range (unless otherwise noted)†
Continuous input voltage range, VIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.3 V to 16 V
ON/OFF input voltage range, VON/OFF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.3 V to 16 V
Output voltage range (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.3 V to 9 V
Input/output voltage differential range, VIN-VOUT (see Note 2) . . . . . . . . . . . . . . . . . . . . . . . . . . −0.3 V to 16 V
Output current, IO (see Note 3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Internally limited (short-circuit protected)
Package thermal impedance, θJA (see Notes 3 and 4): DBV package . . . . . . . . . . . . . . . . . . . . . . . . 206°C/W
YEQ/YZQ package . . . . . . . . . . . . . . . . . . TBD°C/W
YEU/YZU package . . . . . . . . . . . . . . . . . . . TBD°C/W
Operating virtual junction temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150°C
Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −65°C to 150°C
† Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTES: 1. If load is returned to a negative power supply in a dual-supply system, the output must be diode clamped to GND.
2. The PNP pass transistor has a parasitic diode connected between the input and output. This diode normally is reverse biased
(VIN > VOUT), but will be forward biased if the output voltage exceeds the input voltage by a diode drop (see Application Information
for more details).
3. Maximum power dissipation is a function of TJ(max), JA, and TA. The maximum allowable power dissipation at any allowable
ambient temperature is PD = (TJ(max) − TA)/JA. Operating at the absolute maximum TJ of 150°C can affect reliability.
4. The package thermal impedance is calculated in accordance with JESD 51-7.
recommended operating conditions
MIN
MAX
VIN
VON/OFF
Supply input voltage
‡
16
V
ON/OFF input voltage
0
V
IOUT
Output current
VIN
150
mA
−40
125
°C
Virtual junction temperature
TJ
‡ Recommended minimum VIN is the greater of:
a) 2.5 V or
b) VOUT(max) + rated dropout voltage (max) for operating IL.
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UNIT
7
SLVS522C − JULY 2004 − REVISED OCTOBER 2004
electrical characteristics at specified virtual junction temperature range,
VIN = VOUT (nominal) + 1 V, VON/OFF = 2 V, CIN = 1 mF, IL = 1 mA, COUT = 4.7 mF (unless otherwise noted)
LP2985A-XX
PARAMETER
TEST CONDITIONS
IL = 1 mA
nVOUT
Output voltage
tolerance
1 mA ≤ IL ≤ 50 mA
1 mA ≤ IL ≤ 150 mA
Line regulation
TJ
MIN
1
−1.5
1.5
−2.5
2.5
−40°C to 125°C
−2.5
2.5
−3.5
25°C
−2.5
2.5
−3.0
3.5 %VNOM
3.0
−40°C to 125°C
−3.5
3.5
−4.0
0.007
1
−40°C to 125°C
IL = 50 mA
−40°C to 125°C
IL = 150 mA
−40°C to 125°C
7
280
65
75
120
350
−40°C to 125°C
VON/OFF < 0.15 V (OFF)
VON/OFF
ON/OFF input
voltage
(see Note 6)
850
−40°C to 125°C
VON/OFF < 0.3 V (OFF)
VON/OFF = HIGH !
O/P ON
VON/OFF = LOW !
O/P OFF
ON/OFF input
current
VON/OFF = 0
VON/OFF = 5 V
60
90
150
120
225
350
280
350
575
95
65
95
125
110
75
110
170
220
120
220
400
600
350
600
1500
850
2500
1500
2500
0.8
0.01
0.8
−40°C to 105°C
0.05
2
0.05
2
5
25°C
−40°C to 125°C
5
1.4
1.4
1.6
25°C
1.6
0.55
−40°C to 125°C
−40°C to 125°C
V
0.55
0.15
0.01
−40°C to 125°C
25°C
µA
1000
0.01
−40°C to 125°C
mV
150
25°C
25°C
ION/OFF
40
1000
25°C
IL = 150 mA
15
60
400
25°C
IL = 50 mA
10
170
25°C
Ground pin current
7
%/V
5
10
125
25°C
−40°C to 125°C
3
575
−40°C to 125°C
IL = 10 mA
1
225
25°C
−40°C to 125°C
3
90
120
0.014
0.032
15
40
25°C
IL = 1 mA
4.0
0.007
5
25°C
IL = 10 mA
0.014
0.032
25°C
IGND
UNIT
1.5
−40°C to 125°C
IL = 0
MAX
−1
25°C
Dropout voltage
(see Note 5)
TYP
−1.5
25°C
VIN-VOUT
MIN
25°C
−40°C to 125°C
IL = 1 mA
MAX
25°C
25°C
VIN =
[VOUT(NOM) + 1 V] to 16 V −40°C to 125°C
IL = 0
TYP
LP2985-XX
0.15
0.01
−2
5
−2
5
15
µA
15
NOTES: 5. Dropout voltage is defined as the input-to-output differential at which the output voltage drops 100 mV below the value
measured with a 1-V differential.
6. The ON/OFF input must be properly driven for reliable operation (see Application Information).
8
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SLVS522C − JULY 2004 − REVISED OCTOBER 2004
electrical characteristics at specified virtual junction temperature range,
VIN = VOUT (nominal) + 1 V, VON/OFF = 2 V, CIN = 1 mF, IL = 1 mA, COUT = 4.7 mF (unless otherwise noted)
(continued)
LP2985A-XX
PARAMETER
Vn
Output noise
(RMS)
nVOUT/nVIN
Ripple
rejection
IOUT(PK)
Peak output
current
IOUT(SC)
Short-circuit
current
TEST CONDITIONS
BW = 300 Hz to 50 kHz,
COUT = 10 µF,
CBYPASS = 10 nF
f = 1kHz,
COUT = 10 µF,
CBYPASS = 10 nF
TJ
MIN
TYP
MAX
LP2985-XX
MIN
TYP
MAX
UNIT
25°C
30
30
µV
25°C
45
45
dB
VOUT ≥ VO(NOM) − 5%
25°C
350
350
mA
RL = 0 (steady state)
(see Note 7)
25°C
400
400
mA
NOTE 7: See Typical Characteristics Curve, Short-Circuit Current vs VOUT
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SLVS522C − JULY 2004 − REVISED OCTOBER 2004
APPLICATION INFORMATION
capacitors
input capacitor (Cin)
A minimum value of 1 F (over the entire operating temperature range) is required at the input of the LP2985.
In addition, this input capacitor should be located within 1 cm of the input pin and connected to a clean analog
ground. There are no Equivalent Series Resistance (ESR) requirements for this capacitor, and the capacitance
can be increased without limit.
output capacitor (Cout)
As an advantage over other regulators, the LP2985 permits the use of low-ESR capacitors at the output,
including ceramic capacitors that can have an ESR as low as 5 mΩ. Tantalum and film capacitors also can be
used if size and cost are not issues. The output capacitor also should be located within 1 cm of the output pin
and be returned to a clean analog ground.
As with other PNP LDOs, stability conditions require the output capacitor to have a minimum capacitance and
an ESR that falls within a certain range.
Minimum Cout: 2.2 µF (can be increased without limit to improve transient response stability margin)
ESR − Ω
ESR range: see Figure 1
Load Current − mA
Figure 1. 2.2-V/3.3-µF ESR Curves
It is critical that both the minimum capacitance and ESR requirement be met over the entire operating
temperature range. Depending on the type of capacitors used, both these parameters can vary significantly with
temperature (see capacitor characteristics section).
noise bypass capacitor (Cbypass)
The LP2985 allows for low-noise performance with the use of a bypass capacitor that is connected to the internal
bandgap reference via the BYPASS pin. This high-impedance bandgap circuitry is biased in the microampere
range and, thus, cannot be loaded significantly, otherwise, its output − and, correspondingly, the output of the
regulator − will change. Thus, for best output accuracy, dc leakage current through Cbypass should be minimized
as much as possible and never should exceed 100 nA.
A 10-nF capacitor is recommended for Cbypass; ceramic and film capacitors are well suited for this purpose.
10
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APPLICATION INFORMATION
capacitor characteristics
ceramics
Ceramic capacitors are ideal choices for use on the output of the LP2985 for several reasons. For capacitances
in the range of 2.2 µF to 4.7 µF, ceramic capacitors have the lowest cost and the lowest ESR, making them
choice candidates for filtering high-frequency noise. For instance, a typical 2.2-µF ceramic capacitor has an
ESR in the range of 10 mΩ to 20 mΩ and, thus, satisfies minimum ESR requirements of the regulator.
Ceramic capacitors have one glaring disadvantage that must be taken into account − a poor temperature
coefficient, where the capacitance can vary significantly with temperature. For instance, a large-value ceramic
capacitor (≥2.2 µF) can lose more than half of its capacitance as the temperature rises from 25°C to 85°C. Thus,
a 2.2-µF capacitor at 25°C will drop well below the minimum Cout required for stability, as ambient temperature
rises. For this reason, select an output capacitor that maintains the minimum 2.2 µF required for stability over
the entire operating temperature range. Note that there are some ceramic capacitors that can maintain a ±15%
capacitance tolerance over temperature.
tantalum
Tantalum capacitors can be used at the output of the LP2985, but there are significant disadvantages that could
prohibit their use:
•
•
•
In the 1-µF to 4.7-µF range, tantalum capacitors are more expensive than ceramics of the equivalent
capacitance and voltage ratings.
Tantalum capacitors have higher ESRs than their equivalent-sized ceramic counterparts. Thus, to meet
the ESR requirements, a higher-capacitance tantalum may be required, at the expense of larger size
and higher cost.
The ESR of a tantalum capacitor increases as temperature drops, as much as double from 25°C to
−40°C. Thus, ESR margins must be maintained over the temperature range in order to prevent
regulator instability.
ON/OFF operation
The LP2985 allows for a shutdown mode via the ON/OFF pin. Driving the pin LOW (≤0.3 V) turns the device
OFF; conversely, a HIGH (≥1.6 V) turns the device ON. If the shutdown feature is not used, ON/OFF should be
connected to the input to ensure that the regulator is on at all times. For proper operation, do not leave ON/OFF
unconnected, and apply a signal with a slew rate of ≥40 mV/µs.
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SLVS522C − JULY 2004 − REVISED OCTOBER 2004
APPLICATION INFORMATION
reverse input-output voltage
There is an inherent diode present across the PNP pass element of the LP2985.
VIN
VOUT
With the anode connected to the output, this diode is reverse biased during normal operation, since the input
voltage is higher than the output. However, if the output is pulled higher than the input for any reason, this diode
is forward biased and can cause a parasitic silicon-controlled rectifier (SCR) to latch, resulting in high current
flowing from the output to the input. Thus, to prevent possible damage to the regulator in any application where
the output may be pulled above the input, an external Schottky diode should be connected between the output
and input. With the anode on output, this Schottky limits the reverse voltage across the output and input pins
to 0.3 V, preventing the regulator’s internal diode from forward biasing.
Schottky
VIN
VOUT
LP2985
12
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SLVS522C − JULY 2004 − REVISED OCTOBER 2004
TYPICAL PERFORMANCE CHARACTERISTICS
CIN = 1 F, COUT = 4.7 F, VIN = VOUT(NOM) +1 V, TA = 255C, ON/OFF Pin Is Tied to VIN
(unless otherwise specified)
OUTPUT VOLTAGE
vs
TEMPERATURE
DROPOUT VOLTAGE
vs
TEMPERATURE
0.45
3.345
0.4
150 mA
VO = 3.3 V
Cbyp = 10 nF
0.35
0.3
Dropout − V
Output Voltage − V
3.335
VI = 4.3 V
VO = 3.3 V
Ci = 1 µF
Co = 4.7 µF
IO = 1 mA
3.325
3.315
0.25
0.2
50 mA
0.15
0.1
3.305
10 mA
0.05
1 mA
3.295
−50
−25
0
25
50
75
100
125
0
−50
150
−25
0
Temperature − °C
SHORT-CIRCUIT CURRENT
vs
TIME
Short-Circuit Current − A
0.4
0.5
VI = 6 V
VO = 3.3 V
Ci = 1 µF
Cbyp = 0.01 µF
0.3
0.25
0.2
0.15
0.4
0.35
0.3
0.25
0.2
0.15
0.1
0.1
0.05
0.05
0
500
1000
Time − ms
150
VI = 16 V
VO = 3.3 V
Ci = 1 µF
Cbyp = 0.01 µF
0.45
0.35
0
−500
125
SHORT-CIRCUIT CURRENT
vs
TIME
Short-Circuit Current − A
0.45
100
Figure 3
Figure 2
0.5
25
50
75
Temperature − °C
1500
2000
0
−100
Figure 4
100
300
500
Time − ms
700
Figure 5
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13
SLVS522C − JULY 2004 − REVISED OCTOBER 2004
TYPICAL PERFORMANCE CHARACTERISTICS
CIN = 1 F, COUT = 4.7 F, VIN = VOUT(NOM) +1 V, TA = 255C, ON/OFF Pin Is Tied to VIN
(unless otherwise specified)
SHORT-CIRCUIT CURRENT
vs
OUTPUT VOLTAGE
GROUND-PIN CURRENT
vs
LOAD CURRENT
1200
320
VO = 3.3 V
300
Ground Pin Current − µA
1000
280
ISC − mA
VO = 3.3 V
Cbyp = 10 nF
1100
260
240
900
800
700
600
500
400
300
200
220
100
200
0
0
0.5
1
1.5
2
2.5
Output Voltage − V
3
3.5
20
0
40
Figure 6
140
160
RIPPLE REJECTION
vs
FREQUENCY
100
100
VI = 5 V
VO = 3.3 V
Co = 10 µF
Cbyp = 0 nF
80
70
80
50 mA
1 mA
60
50
40
VI = 3.7 V
VO = 3.3 V
Co = 10 µF
Cbyp = 0 nF
90
Ripple Rejection − dB
90
Ripple Rejection − dB
120
Figure 7
RIPPLE REJECTION
vs
FREQUENCY
150 mA
30
70
1 mA
60
50
50 mA
40
30
20
20
10
10
0
150 mA
0
10
100
1K
10K
100K
1M
10
Frequency − Hz
100
1K
Figure 9
POST OFFICE BOX 655303
10K
Frequency − Hz
Figure 8
14
60
80
100
Load Current − mA
• DALLAS, TEXAS 75265
100K
1M
SLVS522C − JULY 2004 − REVISED OCTOBER 2004
TYPICAL PERFORMANCE CHARACTERISTICS
CIN = 1 F, COUT = 4.7 F, VIN = VOUT(NOM) +1 V, TA = 255C, ON/OFF Pin Is Tied to VIN
(unless otherwise specified)
RIPPLE REJECTION
vs
FREQUENCY
RIPPLE REJECTION
vs
FREQUENCY
100
80
80
70
1 mA
60
50
40
50 mA
30
20
VI = 5 V
VO = 3.3 V
Co = 4.7 µF
Cbyp = 10 nF
90
Ripple Rejection − dB
90
Ripple Rejection − dB
100
VI = 5 V
VO = 3.3 V
Co = 4.7 µF
Cbyp = 10 nF
70
1 mA
60
10 mA
50
40
100 mA
30
20
150 mA
10
10
0
10
100
1K
10K
100K
0
1M
10
100
1K
10K
Frequency − Hz
Frequency − Hz
Figure 10
OUTPUT IMPEDANCE
vs
FREQUENCY
10
Ci = 1 µF
Co = 10 µF
VO = 3.3 V
1
1 mA
Output Impedance − Ω
Output Impedance − Ω
1
10 mA
100 mA
0.1
0.01
0.001
10
100
1K
1M
Figure 11
OUTPUT IMPEDANCE
vs
FREQUENCY
10
100K
10K
100K
1M
Ci = 1 µF
Co = 4.7 µF
VO = 3.3 V
1 mA
10 mA
100 mA
0.1
0.01
0.001
10
100
1K
10K
100K
1M
Frequency − Hz
Frequency − Hz
Figure 13
Figure 12
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15
SLVS522C − JULY 2004 − REVISED OCTOBER 2004
TYPICAL PERFORMANCE CHARACTERISTICS
CIN = 1 F, COUT = 4.7 F, VIN = VOUT(NOM) +1 V, TA = 255C, ON/OFF Pin Is Tied to VIN
(unless otherwise specified)
OUTPUT NOISE DENSITY
vs
FREQUENCY
OUTPUT NOISE DENSITY
vs
FREQUENCY
10
10
ILOAD = 1 mA
1
Noise Density − nV/ Hz
Noise Density − nV/ Hz
ILOAD = 150 mA
Cbyp = 100 nF
Cbyp = 1 nF
0.1
Cbyp = 10 nF
1
Cbyp = 100 nF
Cbyp = 1 nF
0.1
Cbyp = 10 nF
0.01
0.01
0.1
1
10
Frequency − kHz
0.1
100
1
Figure 14
10
Frequency − kHz
100
Figure 15
GROUND-PIN CURRENT
vs
TEMPERATURE
INPUT CURRENT
vs
INPUT VOLTAGE
1400
1.8
VO = 3.3 V
Cbyp = 10 nF
1.6
1200
RL = 3.3 kΩ
VO = 3.3 V
Cbyp = 10 nF
150 mA
Ground Current − C
Input Current − mA
1.4
1.2
1
0.8
RL = Open
0.6
1000
800
600
1 mA
400
50 mA
0.4
0 mA
200
0.2
0
10 mA
0
0
1
2
3
4
5
6
−50
−25
25
50
75
Temperature − °C
Input Voltage − V
Figure 17
Figure 16
16
0
POST OFFICE BOX 655303
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100
125
150
SLVS522C − JULY 2004 − REVISED OCTOBER 2004
TYPICAL PERFORMANCE CHARACTERISTICS
CIN = 1 F, COUT = 4.7 F, VIN = VOUT(NOM) +1 V, TA = 255C, ON/OFF Pin Is Tied to VIN
(unless otherwise specified)
3.4
200
3.38
150
3.38
150
3.36
100
3.36
100
3.32
3.3
50
IL
VO = 3.3 V
Cbyp = 10 nF
∆IL = 100 mA
0
−50
VO
3.28
−100
3.26
IL
3.34
3.32
3.3
VO = 3.3 V
Cbyp = 10 nF
∆IL = 150 mA
0
−50
VO
3.28
−100
−150
3.26
−150
3.24
−200
3.24
−200
3.22
−250
3.22
−250
20 µs/div"
20 µs/div"
Figure 19
Figure 18
LOAD TRANSIENT RESPONSE
LINE TRANSIENT RESPONSE
200
3.38
150
3.36
100
IL
3.34
3.32
3.3
VO = 3.3 V
Cbyp = 0 nF
∆IL = 150 mA
0
−50
VO
3.28
50
−100
3.26
−150
3.24
−200
3.22
−250
3.41
5.5
3.39
5
VI
3.37
Output Voltage − V
3.4
Load Current − mA
Output Voltage − V
50
3.35
VO = 3.3 V
Cbyp = 0 nF
IO = 150 mA
4.5
4
3.5
3.33
3.31
VO
3
3.29
2.5
3.27
2
20 µs/div"
Input Voltage − V
3.34
Output Voltage − V
200
Load Current − mA
Output Voltage − V
3.4
Load Current − mA
LOAD TRANSIENT RESPONSE
LOAD TRANSIENT RESPONSE
20 µs/div"
Figure 21
Figure 20
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17
SLVS522C − JULY 2004 − REVISED OCTOBER 2004
TYPICAL PERFORMANCE CHARACTERISTICS
CIN = 1 F, COUT = 4.7 F, VIN = VOUT(NOM) +1 V, TA = 255C, ON/OFF Pin Is Tied to VIN
(unless otherwise specified)
LINE TRANSIENT RESPONSE
3.41
5.5
3.39
5
3.39
5
4.5
3.37
3.35
VO = 3.3 V
Cbyp = 10 nF
IO = 150 mA
4
3.33
3.5
3.31
3.29
VO
3.27
3.35
VI
VO = 3.3 V
Cbyp = 0 nF
IO = 1 mA
4.5
Input Voltage − V
VI
3.37
Output Voltage − V
5.5
Input Voltage − V
Output Voltage − V
LINE TRANSIENT RESPONSE
3.41
4
3.33
3.5
3
3.31
3
2.5
3.29
2.5
VO
3.27
2
2
20 µs/div"
20 µs/div"
Figure 22
Figure 23
LINE TRANSIENT RESPONSE
TURN-ON TIME
4
5.5
3.41
10
VO
3
5
3.39
8
VO = 3.3 V
Cbyp = 10 nF
IO = 1 mA
3.5
3.31
VO
1
6
0
−1
3
−2
2.5
−3
2
−4
VO = 3.3 V
Cbyp = 0
IO = 150 mA
4
VON/OFF
3.29
3.27
18
0
100 µs/div"
100 µs/div"
Figure 24
Figure 25
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2
VON/OFF − V
4
3.35
3.33
4.5
Output Voltage − V
Output Voltage − V
3.37
2
Input Voltage − V
VIN
SLVS522C − JULY 2004 − REVISED OCTOBER 2004
TYPICAL PERFORMANCE CHARACTERISTICS
CIN = 1 F, COUT = 4.7 F, VIN = VOUT(NOM) +1 V, TA = 255C, ON/OFF Pin Is Tied to VIN
(unless otherwise specified)
TURN-ON TIME
TURN-ON TIME
10
4
10
4
VO
VO
3
3
8
8
6
0
−1
VO = 3.3 V
Cbyp = 100 pF
ILOAD = 150 mA
4
−2
VON/OFF
1
6
0
−1
VO = 3.3 V
Cbyp = 1 nF
ILOAD = 150 mA
4
VON/OFF − V
1
Output Voltage − V
2
VON/OFF − V
Output Voltage − V
2
VON/OFF
−2
2
2
−3
−3
0
−4
0
−4
2 ms/div"
200 µs/div"
Figure 27
Figure 26
TURN-ON TIME
4
Input
10
3
8
1
6
0
−1
4
VO = 3.3 V
Cbyp = 10 nF
ILOAD = 150 mA
VON/OFF − V
Output Voltage − V
2
Output
−2
2
−3
0
−4
20 ms/div"
Figure 28
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19
SLVS522C − JULY 2004 − REVISED OCTOBER 2004
WAFER CHIP SCALE INFORMATION
LP2985x-xxYEQ NanoStar (0.17-mm Bump)
LP2985x-xxYZQ NanoFree (0.17-mm Pb-Free Bump)
987
1,037
1,287
1,337
Pin A1 Index Area
0,625 Max
0,15
0,10
NOTES: A.
B.
C.
D.
20
All linear dimensions are in millimeters.
This drawing is subject to change without notice.
NanoStar package configuration
This package is tin-lead (SnPb); consult the factory for availability of lead-free material.
POST OFFICE BOX 655303
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0,19
0,15
SLVS522C − JULY 2004 − REVISED OCTOBER 2004
WAFER CHIP SCALE INFORMATION
LP2985x-xxYEU NanoStar (0.30-mm Bump)
LP2985x-xxYZU NanoFree (0.30-mm Pb-Free Bump)
987
1,037
1,287
1,337
Pin A1 Index Area
0,35
0,25
0,75 Max
0,30
0,20
NOTES: A.
B.
C.
D.
All linear dimensions are in millimeters.
This drawing is subject to change without notice.
NanoStar package configuration
This package is tin-lead (SnPb); consult the factory for availability of lead-free material.
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