LTC3260.pdf 데이터시트 (총 18 페이지) - 파일 다운로드 LTC3260 데이타시트 다운로드

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LTC3260
Low Noise Dual Supply
Inverting Charge Pump
Features
n VIN Range: 4.5V to 32V
n Inverting Charge Pump Generates –VIN
n Charge Pump Output Current Up to 100mA
n Low Noise Negative LDO Post Regulator
(ILDO– = 50mA Max)
n Low Noise Independent Positive LDO Regulator
(ILDO+ = 50mA Max)
n 100µA Quiescent Current in Burst Mode® Operation
with Both LDO Regulators On
n 50kHz to 500kHz Programmable Oscillator Frequency
n Stable with Ceramic Capacitors
n Short-Circuit/Thermal Protection
n Low Profile 3mm × 4mm 14-Pin DFN and Thermally
Enhanced 16-Pin MSOP Packages
Applications
n Low Noise Bipolar/Inverting Supplies
n Industrial/Instrumentation Low Noise Bias
Generators
n Portable Medical Equipment
n Portable Instruments
Description
The LTC®3260 is a low noise dual polarity output power
supply that includes an inverting charge pump with both
positive and negative LDO regulators. The charge pump
operates over a wide 4.5V to 32V input range and can deliver
up to 100mA of output current. Each LDO regulator can
provide up to 50mA of output current. The negative LDO
post regulator is powered from the charge pump output.
The LDO output voltages can be adjusted using external
resistor dividers.
The charge pump employs either low quiescent current
Burst Mode operation or low noise constant frequency
mode. In Burst Mode operation the charge pump VOUT
regulates to –0.94 • VIN, and the LTC3260 draws only
100µA of quiescent current with both LDO regulators on.
In constant frequency mode the charge pump produces
an output equal to –VIN and operates at a fixed 500kHz
or to a programmed value between 50kHz to 500kHz us-
ing an external resistor. The LTC3260 is available in low
profile (0.75mm) 3mm x 4mm 14-pin DFN and thermally
enhanced 16-pin MSOP packages.
L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks
and ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the
property of their respective owners.
Typical Application
±12V Outputs from a Single 15V Input
15V
–15V
10µF
1µF
VIN LDO+
LTC3260
EN+ ADJ+
ENBYP+
MODE
C+
C
GND
BYP
ADJ
VOUT
LDO
10µF
RT
200k
12V
10µF 909k
10nF
10nF
100k
100k
10µF
3260 TA01a
909k
–12V
LDO Rejection of VOUT Ripple
VLDO+
10mV/DIV
AC-COUPLED
VLDO–
10mV/DIV
AC-COUPLED
VOUT
10mV/DIV
AC-COUPLED
VVVILLNDDOO=+–1==5V1–21V2V
IfIOLLDDSOOC+–==–5550000mmkHAAz
1µs/DIV
3260 TA01b
3260fa
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LTC3260
Absolute Maximum Ratings (Notes 1, 3)
LVDINO, +EN...+..,..E..N....,..M...O..D...E......................................................................–.–01.63VV
to
to
36V
36V
RVOT,UAT,DLJD+O......................................................................................................–. –360.V3Vtoto0.63VV
BYP+.......................................................... –0.3V to 2.5V
ADJ............................................................. –6V to 0.3V
BYP.......................................................... –2.5V to 0.3V
VOUT, LDO+, LDOShort-Circuit Duration......... Indefinite
Operating Junction Temperature Range
(Note 2)................................................... –55°C to 150°C
Storage Temperature Range.................. –65°C to 150°C
Lead Temperature (Soldering, 10 sec)
MSE Only........................................................... 300°C
Pin Configuration
EN+
RT
BYP
ADJ
LDO
VOUT
C
1
2
3
4
5
6
7
TOP VIEW
15
GND
14 BYP+
13 ADJ+
12 MODE
11 EN
10 LDO+
9 VIN
8 C+
DE PACKAGE
14-LEAD (4mm × 3mm) PLASTIC DFN
TJMAX = 150°C, θJA = 43°C/W
EXPOSED PAD (PIN 15) IS GND, MUST BE SOLDERED TO PCB
EN+ 1
LBADYDROPJT–––
2
3
4
5
VOCU–T
6
7
NC 8
TOP VIEW
17
GND
16
15
BAYDPJ++
14
13
12
MELNDOOD+E
11
10
VCI+N
9 NC
MSE PACKAGE
16-LEAD PLASTIC MSOP
TJMAX = 150°C, θJA = 43°C/W
EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB
Order Information
LEAD FREE FINISH
TAPE AND REEL
PART MARKING*
PACKAGE DESCRIPTION
TEMPERATURE RANGE
LTC3260EDE#PBF
LTC3260EDE#TRPBF
3260
14-Lead (4mm × 3mm) Plastic DFN
–40°C to 125°C
LTC3260IDE#PBF
LTC3260IDE#TRPBF
3260
14-Lead (4mm × 3mm) Plastic DFN
–40°C to 125°C
LTC3260EMSE#PBF
LTC3260EMSE#TRPBF 3260
16-Lead Plastic MSOP
–40°C to 125°C
LTC3260IMSE#PBF
LTC3260IMSE#TRPBF 3260
16-Lead Plastic MSOP
–40°C to 125°C
LTC3260HMSE#PBF
LTC3260HMSE#TRPBF 3260
16-Lead Plastic MSOP
–40°C to 150°C
LTC3260MPMSE#PBF
LTC3260MPMSE#TRPBF 3260
16-Lead Plastic MSOP
–55°C to 150°C
Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping
container.Consult LTC Marketing for information on non-standard lead based finish parts.
For more information on lead free part marking, go to: http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/
3260fa
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LTC3260
E lectrical Characteristics The l denotes the specifications which apply over the full operating
junction temperature range, otherwise specifications are at TA = 25°C (Note 2). VIN = EN+ = EN= 12V, MODE = 0V, RT = 200kΩ.
SYMBOL PARAMETER
CONDITIONS
MIN TYP MAX UNITS
Charge Pump
VIN Input Voltage Range
l 4.5
32
VUVLO
VIN Undervoltage Lockout Threshold
VVIINN
Rising
Falling
l
l 3.4
3.8
3.6
4
IVIN VIN Quiescent Current
Shutdown, EN+ = EN= 0V
MEMNOODD=EE0==V,VVIIILNND,,OEI+VNO=+U0T=m=0AVIL, DIVOO+U=T
I=LDILOD–O=
= 0mA
0mA
MODE = 0V, IVOUT = 0mA
25
30 50
80 160
100 200
3.5 5.5
VRT RT Regulation Voltage
1.200
VOUT VOUT Regulation Voltage
MODE = 12V
MODE = 0V
–0.94 • VIN
–VIN
fOSC Oscillator Frequency
RT = GND
450 500 550
ROUT Charge Pump Output Impedance MODE = 0V, RT = GND
32
ISHORT_CKT Max IVOUT Short-Circuit Current
VOUT = GND
l 100 160 250
VMODE(H) MODE Threshold Rising
l 1.1 2.0
VMODE(L)
MODE Threshold Falling
l 0.4
1.0
IMODE
MODE Pin Internal Pull-Down Current VIN = MODE = 32V
0.7
50mA Positive Regulator
V
V
V
µA
µA
µA
µA
mA
V
V
V
kHz
Ω
mA
V
V
µA
LDO+ Output Voltage Range
l 1.2
32 V
VADJ+
IADJ+
ILDO+(SC)
ADJ+ Reference Voltage
ADJ+ Input Current
LDO+ Short-Circuit Current
Line Regulation
VADJ+ = 1.2V
l 1.176
–50
l 50
1.200
100
0.04
1.224
50
V
nA
mA
mV/V
Load Regulation
0.03 mV/mA
VDROPOUT+ LDO+ Dropout Voltage
Output Voltage Noise
VEN+(H)
VEN+(L)
IEN+
EN+ Threshold Rising
EN+ Threshold Falling
EN+ Pin Internal Pull-Down Current
50mA Negative Regulator
ILDO+ = 50mA
CBYP+ = 10nF
VIN = EN+ = 32V
400 800
mV
100 µVRMS
l
1.1 2.0
V
l 0.4
1.0
V
0.7 µA
LDOOutput Voltage Range
l –32
–1.2 V
VADJ–
IADJ–
ILDO–(SC)
ADJReference Voltage
ADJInput Current
LDOShort-Circuit Current
Line Regulation
VADJ– = –1.2V
l –1.224 –1.200 –1.176
–50 50
l 50
100
0.002
V
nA
mA
mV/V
Load Regulation
0.02 mV/mA
VDROPOUT–
VEN(H)
VEN(L)
IEN–
LDODropout Voltage
Output Voltage Noise
ENThreshold Rising
ENThreshold Falling
ENPin Internal Pull-Down Current
ILDO– = 50mA
CBYP– = 10nF
VIN = EN= 32V
200 500
mV
100 µVRMS
l
1.1 2.0
V
l 0.4
1.0
V
1.4 µA
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LTC3260
Electrical Characteristics
Note 1: Stresses beyond those listed under Absolute Maximum Ratings
may cause permanent damage to the device. Exposure to any Absolute
Maximum Rating condition for extended periods may affect device
reliability and lifetime.
Note 2: The LTC3260 is tested under pulsed load conditions such that
TJ ≈ TA. The LTC3260E is guaranteed to meet specifications from
0°C to 85°C junction temperature. Specifications over the –40°C to
125°C operating junction temperature range are assured by design,
characterization and correlation with statistical process controls. The
LTC3260I is guaranteed over the –40°C to 125°C operating junction
temperature range, the LTC3260H is guaranteed over the –40°C to 150°C
operating junction temperature range and the LTC3260MP is tested and
guaranteed over the full –55°C to 150°C operating junction temperature
range. Note that the maximum ambient temperature consistent with
these specifications is determined by specific operating conditions in
conjunction with board layout, the rated package thermal impedance and
other environmental factors.
The junction temperature (TJ, in °C) is calculated from the ambient
temperature (TA, in °C) and power dissipation (PD, in Watts) according to
the formula:
TJ = TA + (PD θJA),
where θJA = 43°C/W is the package thermal impedance.
Note 3: This IC includes overtemperature protection that is intended
to protect the device during momentary overload conditions. Junction
temperatures will exceed 150°C when overtemperature protection is
active. Continuous operation above the specified maximum operating
junction temperature may result in device degradation or failure.
Typical Performance Characteristics
(TA = 25°C, CFLY = 1µF, CIN = COUT = CLDO+ = CLDO– = 10µF unless otherwise noted)
Oscillator Frequency
vs Supply Voltage
600
Oscillator Frequency vs RT
600
500 RT = GND
500
400 400
300
RT = 200kΩ
200
300
200
100
0
05
10 15 20 25 30 35
SUPPLY VOLTAGE (V)
3260 G01
Quiescent Current vs Temperature
160 VIN = 12V
140
Burst Mode OPERATION
120 WITH BOTH LDOs ON
100
80
60
Burst Mode OPERATION
WITH NEGATIVE LDO ON
40
20 POSITIVE LDO ON
0
–50 –25
0 25 50 75 100 125 150
TEMPERATURE (°C)
3260 G04
4
100
0
1 10 100 1000 10000
RT (kΩ)
3260 G02
Quiescent Current vs Supply
Voltage (Constant Frequency Mode)
16
14
12
10
8 fOSC = 500kHz
6 fOSC = 200kHz
4
2 fOSC = 50kHz
0
0 5 10 15 20 25 30 35
SUPPLY VOLTAGE (V)
3260 G05
Shutdown Current vs Temperature
30
25
20
15
10 VIN = 32V
5
0
–50 –25
VIN = 12V
VIN = 5V
0 25 50 75 100 125 150
TEMPERATURE (°C)
3260 G03
Quiescent Current vs Temperature
(Constant Frequency Mode)
10
9 VIN = 12V
8 fOSC = 500kHz
7
6
5
4 fOSC = 200kHz
3
2
1
fOSC = 50kHz
0
–50 –25
0 25 50 75 100 125 150
TEMPERATURE (°C)
3260 G06
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Typical Performance Characteristics
(TA = 25°C, CFLY = 1µF, CIN = COUT = CLDO+ = CLDO– = 10µF unless otherwise noted)
Effective Open-Loop Resistance
vs Temperature
60 fOSC = 500kHz
50
40
30
20
10
0
–50 –25
VIN = 32V
VIN = 25V
VIN = 12V
0 25 50 75 100 125 150
TEMPERATURE (°C)
3620 G07
Effective Open-Loop Resistance
vs Supply Voltage
90
80
70 fOSC = 200kHz
60
50
40 fOSC = 500kHz
30
20
10
0
0 5 10 15 20 25 30 35
SUPPLY VOLTAGE (V)
3260 G10
vVsOUSTuSpphloyrtV-Colitracgueit Current
250
200 RT = GND
150
100 RT = 200kΩ
50
0
0 5 10 15 20 25 30 35
SUPPLY VOLTAGE (V)
3260 G08
ADJ+ Pin Voltage vs Temperature
1.224
1.212
1.200
1.188
1.176
–50 –25
0 25 50 75 100 125 150
TEMPERATURE (°C)
3260 G11
LTC3260
vVsolOtaugtpeuLtoCsusrr(eVnINt (–C|oVnOsUtTa|n)t
Frequency Mode)
3.0 VIN = 12V
2.5 fOSC = 200kHz
2.0
fOSC = 50kHz
1.5
1.0
0.5
0
0.1 1
fOSC = 500kHz
10 100
OUTPUT CURRENT (mA)
LDO+ Dropout Voltage
vs Temperature
800
700
VILIDNO=+
12V
= 50mA
3260 G09
600
500
400
300
200
100
0
–50 –25
0 25 50 75 100 125 150
TEMPERATURE (°C)
3260 G12
LDO+ Supply Rejection
60
50
40
30
20
10
IVVLILDNDOO=++6==.555V0VmA
0
VCRLDIPOP+LE=
= 50mVRMS
10µF
0.1 1 10
100
FREQUENCY (kHz)
1000
3260 G13
LDO+ GND Pin Current vs ILOAD
0.14
VIN = 12V
0.12
0.10
0.08
0.06
0.04
0.02
0
0 1 10 100
ILOAD (mA)
3260 G14
LDO+ Load Regulation
1.2006
1.2004
VIN = 12V
UNITY GAIN
1.2002
1.2000
1.1998
1.1996
1.1994
0.1
1 10
ILDO+ (mA)
100
3260 G15
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