Datasheet LT3680 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | 36V, 3.5A, 2.4MHz Step-Down Switching Regulator with 75µA Quiescent Current |
| Pages / Page | 24 / 1 — FEATURES. DESCRIPTION. Wide Input Voltage Range: 3.6V to 36V. 3.5A … |
| Revision | C |
| File Format / Size | PDF / 526 Kb |
| Document Language | English |
FEATURES. DESCRIPTION. Wide Input Voltage Range: 3.6V to 36V. 3.5A Maximum Output Current
Model Line for this Datasheet
Text Version of Document
LT3680 36V, 3.5A, 2.4MHz Step-Down Switching Regulator with 75µA Quiescent Current
FEATURES DESCRIPTION
■
Wide Input Voltage Range: 3.6V to 36V
The LT®3680 is an adjustable frequency (200kHz to ■
3.5A Maximum Output Current
2.4MHz) monolithic buck switching regulator that accepts ■
Low Ripple (<15mVP-P) Burst Mode® Operation:
input voltages up to 36V. A high efficiency 95m switch
IQ = 75µA at 12VIN to 3.3VOUT
is included on the die along with a boost Schottky diode ■
Adjustable Switching Frequency: 200kHz to 2.4MHz
and the necessary oscillator, control, and logic circuitry. ■
Low Shutdown Current: IQ < 0.5µA
Current mode topology is used for fast transient response ■
Integrated Boost Diode
and good loop stability. Low ripple Burst Mode operation ■
Synchronizable Between 250kHz to 2MHz
maintains high efficiency at low output currents while ■ Power Good Flag keeping output ripple below 15mV in a typical application. ■ Saturating Switch Design: 95m On-Resistance In addition, the LT3680 can further enhance low output ■ 0.790V Feedback Reference Voltage current efficiency by drawing bias current from the output ■ Output Voltage: 0.79V to 30V when VOUT is above 3V. Shutdown reduces input supply ■ Thermal Protection current to less than 1µA while a resistor and capacitor on ■ Soft-Start Capability the RUN/SS pin provide a controlled output voltage ramp ■ Small 10-Pin Thermally Enhanced MSOP and (soft-start). A power good flag signals when VOUT reaches (3mm × 3mm) DFN Packages 91% of the programmed output voltage. The LT3680 is available in 10-Pin MSOP and 3mm × 3mm DFN packages
APPLICATIONS
with exposed pads for low thermal resistance. All registered trademarks and trademarks are the property of their respective owners. ■ Automotive Battery Regulation ■ Power for Portable Products ■ Distributed Supply Regulation ■ Industrial Supplies ■ Wall Transformer Regulation
TYPICAL APPLICATION 5V Step-Down Converter Efficiency
V V 100 IN OUT 6.3V TO 36V 5V 3.5A VIN = 12V VIN BD 90 OFF ON RUN/SS BOOST VIN = 34V 80 0.47µF VIN = 24V 15k 4.7µH VC LT3680 SW 10µF 70 RT EFFICIENCY (%) 680pF PG 60 536k VOUT = 5V 63.4k SYNC FB L = 4.7µH GND f = 600kHz 100k 47µF 50 0 0.5 1 1.5 2 2.5 3 3.5 OUTPUT CURRENT (A) 3680 TA01a 3680 G01 Rev C Document Feedback For more information www.analog.com 1 Document Outline Features Applications Description Typical Application 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 Typical Application Related Parts
FEATURES DESCRIPTION
■
Wide Input Voltage Range: 3.6V to 36V
The LT®3680 is an adjustable frequency (200kHz to ■
3.5A Maximum Output Current
2.4MHz) monolithic buck switching regulator that accepts ■
Low Ripple (<15mVP-P) Burst Mode® Operation:
input voltages up to 36V. A high efficiency 95m switch
IQ = 75µA at 12VIN to 3.3VOUT
is included on the die along with a boost Schottky diode ■
Adjustable Switching Frequency: 200kHz to 2.4MHz
and the necessary oscillator, control, and logic circuitry. ■
Low Shutdown Current: IQ < 0.5µA
Current mode topology is used for fast transient response ■
Integrated Boost Diode
and good loop stability. Low ripple Burst Mode operation ■
Synchronizable Between 250kHz to 2MHz
maintains high efficiency at low output currents while ■ Power Good Flag keeping output ripple below 15mV in a typical application. ■ Saturating Switch Design: 95m On-Resistance In addition, the LT3680 can further enhance low output ■ 0.790V Feedback Reference Voltage current efficiency by drawing bias current from the output ■ Output Voltage: 0.79V to 30V when VOUT is above 3V. Shutdown reduces input supply ■ Thermal Protection current to less than 1µA while a resistor and capacitor on ■ Soft-Start Capability the RUN/SS pin provide a controlled output voltage ramp ■ Small 10-Pin Thermally Enhanced MSOP and (soft-start). A power good flag signals when VOUT reaches (3mm × 3mm) DFN Packages 91% of the programmed output voltage. The LT3680 is available in 10-Pin MSOP and 3mm × 3mm DFN packages
APPLICATIONS
with exposed pads for low thermal resistance. All registered trademarks and trademarks are the property of their respective owners. ■ Automotive Battery Regulation ■ Power for Portable Products ■ Distributed Supply Regulation ■ Industrial Supplies ■ Wall Transformer Regulation
TYPICAL APPLICATION 5V Step-Down Converter Efficiency
V V 100 IN OUT 6.3V TO 36V 5V 3.5A VIN = 12V VIN BD 90 OFF ON RUN/SS BOOST VIN = 34V 80 0.47µF VIN = 24V 15k 4.7µH VC LT3680 SW 10µF 70 RT EFFICIENCY (%) 680pF PG 60 536k VOUT = 5V 63.4k SYNC FB L = 4.7µH GND f = 600kHz 100k 47µF 50 0 0.5 1 1.5 2 2.5 3 3.5 OUTPUT CURRENT (A) 3680 TA01a 3680 G01 Rev C Document Feedback For more information www.analog.com 1 Document Outline Features Applications Description Typical Application 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 Typical Application Related Parts
