Datasheet LT3970 (Analog Devices)
| Hersteller | Analog Devices |
| Beschreibung | 40V, 350mA Step-Down Regulator with 2.5μA Quiescent Current and Integrated Diodes |
| Seiten / Seite | 24 / 1 — FEATURES. DESCRIPTION. Low Ripple Burst Mode. Operation. 2.5µA IQ at … |
| Revision | D |
| Dateiformat / Größe | PDF / 706 Kb |
| Dokumentensprache | Englisch |
FEATURES. DESCRIPTION. Low Ripple Burst Mode. Operation. 2.5µA IQ at 12VIN to 3.3VOUT. Output Ripple < 5mVP-P
Modelllinie für dieses Datenblatt
- LT3970EDDB#TRMPBF LT3970EDDB#TRPBF LT3970EDDB-3.3#TRMPBF LT3970EDDB-3.3#TRPBF LT3970EDDB-3.42#TRMPBF LT3970EDDB-3.42#TRPBF LT3970EDDB-5#TRMPBF LT3970EDDB-5#TRPBF LT3970EMS#PBF LT3970EMS#TRPBF LT3970EMS#WPBF LT3970EMS#WTRPBF LT3970EMS-3.3#PBF LT3970EMS-3.3#TRPBF LT3970EMS-3.3#WPBF LT3970EMS-3.3#WTRPBF LT3970EMS-5#PBF LT3970EMS-5#TRPBF LT3970EMS-5#WPBF LT3970EMS-5#WTRPBF LT3970HMS#PBF LT3970HMS#TRPBF LT3970HMS#WPBF LT3970HMS#WTRPBF LT3970HMS-3.3#PBF LT3970HMS-3.3#TRPBF LT3970HMS-3.3#WPBF LT3970HMS-3.3#WTRPBF LT3970HMS-5#PBF LT3970HMS-5#TRPBF LT3970HMS-5#WPBF LT3970HMS-5#WTRPBF LT3970IDDB#TRMPBF LT3970IDDB#TRPBF LT3970IDDB-3.3#TRMPBF LT3970IDDB-3.3#TRPBF LT3970IDDB-5#TRMPBF LT3970IDDB-5#TRPBF LT3970IMS#PBF LT3970IMS#TRPBF LT3970IMS#WPBF LT3970IMS#WTRPBF LT3970IMS-3.3#PBF LT3970IMS-3.3#TRPBF LT3970IMS-3.3#WPBF LT3970IMS-3.3#WTRPBF LT3970IMS-5#PBF LT3970IMS-5#TRPBF LT3970IMS-5#WPBF LT3970IMS-5#WTRPBF
Textversion des Dokuments
LT3970 Series 40V, 350mA Step-Down Regulator with 2.5µA Quiescent Current and Integrated Diodes
FEATURES DESCRIPTION
n
Low Ripple Burst Mode
®
Operation
The LT®3970 is an adjustable frequency monolithic buck n
2.5µA IQ at 12VIN to 3.3VOUT
switching regulator that accepts a wide input voltage n
Output Ripple < 5mVP-P
range up to 40V, and consumes only 2.5µA of quiescent n
Wide Input Voltage Range: 4.2V to 40V Operating
current. A high efficiency switch is included on the die n
Adjustable Switching Frequency: 200kHz to 2.2MHz
along with the catch diode, boost diode, and the neces- n
Integrated Boost and Catch Diodes
sary oscillator, control and logic circuitry. Low ripple Burst n
350mA Output Current
Mode operation maintains high efficiency at low output n
Fixed Output Voltages: 3.3V, 3.42V, 5V
currents while keeping the output ripple below 5mV in
1.8µA IQ at 12VIN
a typical application. Current mode topology is used for n Accurate 1V Enable Pin Threshold fast transient response and good loop stability. A catch n Low Shutdown Current: IQ = 0.7µA diode current limit provides protection against shorted n Internal Sense Limits Catch Diode Current outputs and overvoltage conditions. An enable pin with n Power Good Flag accurate threshold is available, producing a low shutdown n Output Voltage: 1.21V to 25V current of 0.7µA. A power good flag signals when VOUT n Internal Compensation reaches 90% of the programmed output voltage. The n Small 10-Pin MSOP and (3mm × 2mm) DFN Packages LT3970 is available in small 10-pin MSOP and 3mm × n AEC-Q100 Qualified for Automotive Applications 2mm DFN packages.
APPLICATIONS
All registered trademarks and trademarks are the property of their respective owners. n Automotive Battery Regulation n Power for Portable Products n Industrial Supplies
TYPICAL APPLICATION Efficiency 5V Step-Down Converter
90 1000 VIN = 12V VIN 6V TO 40V 0.22µF 80 100 V POWER LOSS (mW) IN BOOST LT3970 22µH VOUT 70 10 OFF ON EN SW 5V PG 350mA BD 22pF 1M 60 1 EFFICIENCY (%) 2.2µF RT FB 22µF GND 226k 316k 50 0.1 f = 600kHz 3490 TA01a 40 0.01 0.01 0.1 1 10 100 LOAD CURRENT (mA) 3970 TA01b Rev. D Document Feedback For more information www.analog.com 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Related Parts
FEATURES DESCRIPTION
n
Low Ripple Burst Mode
®
Operation
The LT®3970 is an adjustable frequency monolithic buck n
2.5µA IQ at 12VIN to 3.3VOUT
switching regulator that accepts a wide input voltage n
Output Ripple < 5mVP-P
range up to 40V, and consumes only 2.5µA of quiescent n
Wide Input Voltage Range: 4.2V to 40V Operating
current. A high efficiency switch is included on the die n
Adjustable Switching Frequency: 200kHz to 2.2MHz
along with the catch diode, boost diode, and the neces- n
Integrated Boost and Catch Diodes
sary oscillator, control and logic circuitry. Low ripple Burst n
350mA Output Current
Mode operation maintains high efficiency at low output n
Fixed Output Voltages: 3.3V, 3.42V, 5V
currents while keeping the output ripple below 5mV in
1.8µA IQ at 12VIN
a typical application. Current mode topology is used for n Accurate 1V Enable Pin Threshold fast transient response and good loop stability. A catch n Low Shutdown Current: IQ = 0.7µA diode current limit provides protection against shorted n Internal Sense Limits Catch Diode Current outputs and overvoltage conditions. An enable pin with n Power Good Flag accurate threshold is available, producing a low shutdown n Output Voltage: 1.21V to 25V current of 0.7µA. A power good flag signals when VOUT n Internal Compensation reaches 90% of the programmed output voltage. The n Small 10-Pin MSOP and (3mm × 2mm) DFN Packages LT3970 is available in small 10-pin MSOP and 3mm × n AEC-Q100 Qualified for Automotive Applications 2mm DFN packages.
APPLICATIONS
All registered trademarks and trademarks are the property of their respective owners. n Automotive Battery Regulation n Power for Portable Products n Industrial Supplies
TYPICAL APPLICATION Efficiency 5V Step-Down Converter
90 1000 VIN = 12V VIN 6V TO 40V 0.22µF 80 100 V POWER LOSS (mW) IN BOOST LT3970 22µH VOUT 70 10 OFF ON EN SW 5V PG 350mA BD 22pF 1M 60 1 EFFICIENCY (%) 2.2µF RT FB 22µF GND 226k 316k 50 0.1 f = 600kHz 3490 TA01a 40 0.01 0.01 0.1 1 10 100 LOAD CURRENT (mA) 3970 TA01b Rev. D Document Feedback For more information www.analog.com 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Related Parts