Datasheet LT3999 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | Low Noise, 1A, 1MHz Push-Pull DC/DC Driver with Duty Cycle Control |
| Pages / Page | 16 / 1 — FEATURES. DESCRIPTION. Wide Input Operating Range: 2.7V to 36V. Dual 1A … |
| File Format / Size | PDF / 310 Kb |
| Document Language | English |
FEATURES. DESCRIPTION. Wide Input Operating Range: 2.7V to 36V. Dual 1A Switches with Programmable Current Limit
Model Line for this Datasheet
Text Version of Document
LT3999 Low Noise, 1A, 1MHz Push-Pull DC/DC Driver with Duty Cycle Control
FEATURES DESCRIPTION
n
Wide Input Operating Range: 2.7V to 36V
The LT®3999 is a monolithic, high voltage, high frequency n
Dual 1A Switches with Programmable Current Limit
DC/DC transformer driver providing isolated power in a n
Programmable Switching Frequency: 50kHz to 1MHz
small solution footprint. n
Frequency Synchronization Up to 1MHz
The LT3999 has two 1A current limited power switches n
∆
VIN Compensation Using Duty Cycle Control
that switch out of phase. The duty cycle is programmable n Low Noise Topology to adjust the output voltage. The switching frequency is n Programmable Input Over and Undervoltage Lockout programmed up to 1MHz and can be synchronized to an n Cross Conduction Prevention Circuitry external clock for more accurate placement of switcher n Programmable Soft-Start harmonics. The input operating range is programmed n Low Shutdown Current: <1µA with the precision undervoltage and overvoltage lockouts. n 10-Lead MSOP and DFN Packages The supply current is reduced to less than 1µA during shutdown. A user-defined RC time constant provides an
APPLICATIONS
adjustable soft-start capability by limiting the inrush cur- n rent at start-up. Low Noise Isolated Supplies n Medical Instrument and Safety The LT3999 is available in a 10-lead MSOP and 3mm × n Distributed Power 3mm DFN package with exposed pad. n Multiple Output Supplies L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear n Positive-to-Negative Supplies Technology Corporation. All other trademarks are the property of their respective owners. n Noise Immunity in Data Acquisition, RS232 and RS485
TYPICAL APPLICATION 12V to 12V, 10W Low Noise Isolated DC/DC Converter LT3999 Line Regulation with Duty Cycle Control
VIN 16 12V 10µF 16V VIN 15.3µH V 15 OUT SYNC SWA 12V • • 14 255k UVLO 10µF 0.8A OVLO/DC 16V 13 I I OUT = 200mA OUT = 400mA 10k RDC 12 LT3999 • • 15.8k IOUT = 800mA 11 SWB 3999 TA01a RT OUTPUT VOLTAGE (V) 10 ILIM/SS RBIAS 9 28k GND 0.1µF 49.9k 500kHz 810 11 12 13 14 15 16 17 18 INPUT VOLTAGE (V) 3999 TA01b 3999fa For more information www.linear.com/LT3999 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 Package Description Typical Application Related Parts
FEATURES DESCRIPTION
n
Wide Input Operating Range: 2.7V to 36V
The LT®3999 is a monolithic, high voltage, high frequency n
Dual 1A Switches with Programmable Current Limit
DC/DC transformer driver providing isolated power in a n
Programmable Switching Frequency: 50kHz to 1MHz
small solution footprint. n
Frequency Synchronization Up to 1MHz
The LT3999 has two 1A current limited power switches n
∆
VIN Compensation Using Duty Cycle Control
that switch out of phase. The duty cycle is programmable n Low Noise Topology to adjust the output voltage. The switching frequency is n Programmable Input Over and Undervoltage Lockout programmed up to 1MHz and can be synchronized to an n Cross Conduction Prevention Circuitry external clock for more accurate placement of switcher n Programmable Soft-Start harmonics. The input operating range is programmed n Low Shutdown Current: <1µA with the precision undervoltage and overvoltage lockouts. n 10-Lead MSOP and DFN Packages The supply current is reduced to less than 1µA during shutdown. A user-defined RC time constant provides an
APPLICATIONS
adjustable soft-start capability by limiting the inrush cur- n rent at start-up. Low Noise Isolated Supplies n Medical Instrument and Safety The LT3999 is available in a 10-lead MSOP and 3mm × n Distributed Power 3mm DFN package with exposed pad. n Multiple Output Supplies L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear n Positive-to-Negative Supplies Technology Corporation. All other trademarks are the property of their respective owners. n Noise Immunity in Data Acquisition, RS232 and RS485
TYPICAL APPLICATION 12V to 12V, 10W Low Noise Isolated DC/DC Converter LT3999 Line Regulation with Duty Cycle Control
VIN 16 12V 10µF 16V VIN 15.3µH V 15 OUT SYNC SWA 12V • • 14 255k UVLO 10µF 0.8A OVLO/DC 16V 13 I I OUT = 200mA OUT = 400mA 10k RDC 12 LT3999 • • 15.8k IOUT = 800mA 11 SWB 3999 TA01a RT OUTPUT VOLTAGE (V) 10 ILIM/SS RBIAS 9 28k GND 0.1µF 49.9k 500kHz 810 11 12 13 14 15 16 17 18 INPUT VOLTAGE (V) 3999 TA01b 3999fa For more information www.linear.com/LT3999 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 Package Description Typical Application Related Parts
