Document
LTC3260 Low Noise Dual Supply Inverting Charge Pump FEATURES
VIN Range: 4.5V to 32V n Inverting Charge Pump Generates –V IN 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
n
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 using 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.
www.DataSheet.co.kr
APPLICATIONS
Low Noise Bipolar/Inverting Supplies n Industrial/Instrumentation Low Noise Bias Generators n Portable Medical Equipment n Portable Instruments
n
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 VIN EN+ EN– MODE 1µF C+ C– VOUT RT 200k LDO+ LTC3260 ADJ+ BYP+ GND BYP– ADJ
–
LDO Rejection of VOUT Ripple
10µF
10µF
12V 909k 100k 100k 909k
VLDO+ 10mV/DIV AC-COUPLED VLDO– 10mV/DIV AC-COUPLED VOUT 10mV/DIV AC-COUPLED VIN = 15V VLDO+ = 12V VLDO– = –12V fOSC = 500kHz ILDO+ = 50mA ILDO– –50mA 1µs/DIV
3260 TA01b
10nF 10nF
–15V
10µF
LDO–
10µF
3260 TA01a
–12V
3260f
1
Datasheet pdf - http://www.DataSheet4U.net/
LTC3260 ABSOLUTE MAXIMUM RATINGS
(Notes 1, 3)
VIN, EN+, EN–, MODE.................................. –0.3V to 36V LDO+ ............................................................–16V to 36V VOUT, LDO – ................................................ –36V to 0.3V RT, ADJ+....................................................... –0.3V to 6V BYP+.......................................................... –0.3V to 2.5V ADJ –............................................................. –6V to 0.3V BYP–.......................................................... –2.5V to 0.3V
VOUT, LDO+, LDO – Short-Circuit Duration......... Indefinite Operating Junction Temperature Range (Note 2)................................................... –40°C to 125°C Storage Temperature Range.................. –65°C to 150°C Lead Temperature (Soldering, 10 sec) MSE Only........................................................... 300°C
PIN CONFIGURATION
TOP VIEW EN+ RT BYP– ADJ– LDO– VOUT C– 1 2 3 4 5 6 7 15 GND 14 BYP+ 13 ADJ+ 12 MODE 11 EN– 10 LDO+ 9 VIN 8 C+ TOP VIEW EN+ RT BYP– ADJ– LDO– VOUT C– NC 1 2 3 4 5 6 7 8 16 15 14 13 12 11 10 9 BYP+ ADJ+ MODE EN– LDO+ VIN C+ NC
17 GND
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
www.DataSheet.co.kr
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 LTC3260EDE#PBF LTC3260IDE#PBF LTC3260EMSE#PBF LTC3260IMSE#PBF TAPE AND REEL LTC3260EDE#TRPBF LTC3260IDE#TRPBF LTC3260EMSE#TRPBF LTC3260IMSE#TRPBF PART MARKING* 3260 3260 3260 3260 PACKAGE DESCRIPTION 14-Lead (4mm × 3mm) Plastic DFN 14-Lead (4mm × 3mm) Plastic DFN 16-Lead Plastic MSOP 16-Lead Plastic MSOP TEMPERATURE RANGE –40°C to 125°C –40°C to 125°C –40°C to 125°C –40°C to 125°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/
3260f
2
Datasheet pdf - http://www.DataSheet4U.net/
LTC3260 ELECTRICAL CHARACTERISTICS
SYMBOL Charge Pump VIN VUVLO IVIN Input Voltage Range VIN Undervoltage Lockout Threshold VIN Quiescent Current VIN Risi.