Datasheet LT8570, LT8570-1 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | Boost/SEPIC/Inverting DC/DC Converter with 65V Switch, Soft-Start and Synchronization |
| Pages / Page | 34 / 1 — FEATURES. DESCRIPTION. 65V Power Switch. Current Limit Options of 0.5A … |
| File Format / Size | PDF / 906 Kb |
| Document Language | English |
FEATURES. DESCRIPTION. 65V Power Switch. Current Limit Options of 0.5A (LT8570) or 0.25A. (LT8570-1)
Model Line for this Datasheet
- LT8570EDD#PBF LT8570EDD#PBF LT8570EDD#TRPBF LT8570EDD#TRPBF LT8570EDD-1#PBF LT8570EDD-1#TRPBF LT8570EMS8E#PBF LT8570EMS8E#PBF LT8570EMS8E#TRPBF LT8570EMS8E#TRPBF LT8570EMS8E-1#PBF LT8570EMS8E-1#TRPBF LT8570HDD#PBF LT8570HDD-1#PBF LT8570HMS8E#PBF LT8570HMS8E-1#PBF LT8570IDD#PBF LT8570IDD#PBF LT8570IDD#TRPBF LT8570IDD#TRPBF LT8570IDD-1#PBF LT8570IDD-1#TRPBF LT8570IMS8E#PBF LT8570IMS8E#PBF LT8570IMS8E#TRPBF LT8570IMS8E#TRPBF LT8570IMS8E-1#PBF LT8570IMS8E-1#TRPBF
Text Version of Document
LT8570/LT8570-1 Boost/SEPIC/Inverting DC/DC Converter with 65V Switch, Soft-Start and Synchronization
FEATURES DESCRIPTION
n
65V Power Switch
The LT®8570 and LT8570-1 are PWM DC/DC converters. n
Current Limit Options of 0.5A (LT8570) or 0.25A
The LT8570 contains a 0.5A, 65V power switch, while
(LT8570-1)
the LT8570-1 contains a 0.25A, 65V power switch. The n
Adjustable Switching Frequency
LT8570 and LT8570-1 can be configured as either a boost, n
Single Feedback Resistor Sets VOUT
SEPIC or inverting converter. n
Synchronizable to External Clock
The LT8570/LT8570-1 have an adjustable oscillator, set n High Gain SHDN Pin Accepts Slowly Varying by a resistor from the RT pin to ground. Additionally, the Input Signals LT8570/LT8570-1 can be synchronized to an external n Wide Input Voltage Range: 2.55V to 40V clock. The switching frequency of the part may be free n Low VCESAT Switch running or synchronized, and can be set between 200kHz n Integrated Soft-Start Function and 1.5MHz. n Easily Configurable as a Boost, SEPIC, or Inverting Converter The LT8570/LT8570-1 also feature innovative SHDN pin n User Configurable Undervoltage Lockout (UVLO) circuitry that allows for slowly varying input signals and n Pin Compatible with LT3580 and LT8580 an adjustable undervoltage lockout function. n Tiny Thermally Enhanced 8-Lead 3mm × 3mm DFN Additional features such as frequency foldback and soft- and 8-Lead MSOP Packages start are integrated. The LT8570/LT8570-1 are available
APPLICATIONS
in tiny thermally enhanced 3mm × 3mm 8-lead DFN and 8-lead MSOP packages. n VFD Bias Supplies L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and n TFT-LCD Bias Supplies ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 7579816. n GPS Receivers n DSL Modems n Local Power Supply
TYPICAL APPLICATION Efficiency and Power Loss 1.5MHz, 5V to 12V Boost Converter
100 320 22µH VOUT VIN 90 280 12V 5V 125mA 80 240 10k POWER LOSS (mW) 70 200 VIN SW 130k 60 160 SHDN FBX 2.2µF 1µF LT8570 EFFICIENCY (%) 50 120 SYNC VC 40 80 6.19k RT GND SS 47pF 30 EFFICIENCY 40 POWER LOSS 56.2k 0.1µF 2.2nF 20 0 8570 TA01a 0 25 50 75 100 125 LOAD CURRENT (mA) 8570 TA01b 85701fa For more information www.linear.com/LT8570 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 Typical Application Related Parts
FEATURES DESCRIPTION
n
65V Power Switch
The LT®8570 and LT8570-1 are PWM DC/DC converters. n
Current Limit Options of 0.5A (LT8570) or 0.25A
The LT8570 contains a 0.5A, 65V power switch, while
(LT8570-1)
the LT8570-1 contains a 0.25A, 65V power switch. The n
Adjustable Switching Frequency
LT8570 and LT8570-1 can be configured as either a boost, n
Single Feedback Resistor Sets VOUT
SEPIC or inverting converter. n
Synchronizable to External Clock
The LT8570/LT8570-1 have an adjustable oscillator, set n High Gain SHDN Pin Accepts Slowly Varying by a resistor from the RT pin to ground. Additionally, the Input Signals LT8570/LT8570-1 can be synchronized to an external n Wide Input Voltage Range: 2.55V to 40V clock. The switching frequency of the part may be free n Low VCESAT Switch running or synchronized, and can be set between 200kHz n Integrated Soft-Start Function and 1.5MHz. n Easily Configurable as a Boost, SEPIC, or Inverting Converter The LT8570/LT8570-1 also feature innovative SHDN pin n User Configurable Undervoltage Lockout (UVLO) circuitry that allows for slowly varying input signals and n Pin Compatible with LT3580 and LT8580 an adjustable undervoltage lockout function. n Tiny Thermally Enhanced 8-Lead 3mm × 3mm DFN Additional features such as frequency foldback and soft- and 8-Lead MSOP Packages start are integrated. The LT8570/LT8570-1 are available
APPLICATIONS
in tiny thermally enhanced 3mm × 3mm 8-lead DFN and 8-lead MSOP packages. n VFD Bias Supplies L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and n TFT-LCD Bias Supplies ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 7579816. n GPS Receivers n DSL Modems n Local Power Supply
TYPICAL APPLICATION Efficiency and Power Loss 1.5MHz, 5V to 12V Boost Converter
100 320 22µH VOUT VIN 90 280 12V 5V 125mA 80 240 10k POWER LOSS (mW) 70 200 VIN SW 130k 60 160 SHDN FBX 2.2µF 1µF LT8570 EFFICIENCY (%) 50 120 SYNC VC 40 80 6.19k RT GND SS 47pF 30 EFFICIENCY 40 POWER LOSS 56.2k 0.1µF 2.2nF 20 0 8570 TA01a 0 25 50 75 100 125 LOAD CURRENT (mA) 8570 TA01b 85701fa For more information www.linear.com/LT8570 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 Typical Application Related Parts
