Datasheet LTC3897 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | PolyPhase Synchronous Boost Controller with Input/Output Protection |
| Pages / Page | 50 / 1 — FEATURES. DESCRIPTION. Input Supply Range: 4.5V to 65V (Up to 75V Surge). … |
| Revision | A |
| File Format / Size | PDF / 3.9 Mb |
| Document Language | English |
FEATURES. DESCRIPTION. Input Supply Range: 4.5V to 65V (Up to 75V Surge). Reverse Input Protection to –40V
Model Line for this Datasheet
Text Version of Document
LTC3897 PolyPhase Synchronous Boost Controller with Input/ Output Protection
FEATURES DESCRIPTION
n
Input Supply Range: 4.5V to 65V (Up to 75V Surge)
The LTC®3897 is a synchronous boost DC/DC controller n
Reverse Input Protection to –40V
with surge stopper and ideal diode controller. n
In-Rush Current Control, Overcurrent Protection
The boost controller drives two N-channel power MOSFET
and Output Disconnect for Boost Converter
stages out-of-phase to reduce input and output capacitor n
Input Voltage Surge Protection with Adjustable
requirements, allowing the use of smaller inductors than
Clamp Voltage
the single-phase equivalent. Synchronous rectification n
Onboard Ideal Diode Controller
reduces power loss and eases thermal requirements. n
Low Quiescent Current: 55µA
n
2-Phase Operation Reduces Required Input and
The surge stopper controls the gate of an external
Output Capacitance and Noise
N-channel MOSFET to protect against high voltage input n
Output Voltage Up to 60V
transients and provides in-rush current control, over- n
Adjustable Gate Drive Level 5V to 10V (OPTI-DRIVE)
current protection and output disconnect for the boost
for Logic-Level or Standard Threshold FETs
converter. The integrated ideal diode controller drives n
No External Bootstrap Diodes Required
another N-channel MOSFET to replace a Schottky diode for reverse input protection and voltage holdup or peak detection. It controls the forward voltage drop across the
APPLICATIONS
MOSFET and minimizes reverse current flow. n Industrial The LTC3897 is available in thermally-enhanced 38-pin n Automotive leadless QFN or 38-lead TSSOP packages. n Military/Avionics All registered trademarks and trademarks are the property of their respective owners. Protected by U.S. patents, including 5408150, 5481178, 5705919, 5929620, 6144194, 6177787, 6580258.
TYPICAL APPLICATION 24V/10A 2-Phase Synchronous Boost Converter with Surge Protection and Reverse Protection Efficiency and Power Loss
REVERSE CURRENT PROTECTION (IDEAL DIODE)
vs Output Current
INPUT VOLTAGE SURGE PROTECTION 5mΩ 3.5µH REVERSE INPUT VOLTAGE PROTECTION IN-RUSH/OVERCURRENT PROTECTION 100 100k BURST EFFICIENCY V 90 IN 2mΩ VBIAS SENSE1+ 6V TO 80 10k 55V 33µF 549k SENSE1– POWER LOSS (mW) 70 SPFB BG1 0.1µF 10Ω 60 1k 12.1k BURST LOSS BOOST1 50 10nF IS– SW1 40 100 IS+ TG1 EFFICIENCY (%) 30 DG 5mΩ 3.5µH VOUT V 24V IN = 12V CS SENSE2+ 20 V 10 10A OUT = 24V SG LTC3897 SENSE2– 10 Burst Mode OPERATION V FIGURE 17 CIRCUIT IN BG2 220µF 0.1µF RUN 0.1µF 0 1 0.001 0.01 0.1 1 10 SS BOOST2 OUTPUT CURRENT (A) 15nF 3897 TA01b 8.66k SW2 ITH 1µF TG2 475k INTV PINS NOT SHOWN IN THIS CIRCUIT: CC VFB PLLIN/MODE, I DRV 3897 TA01a LIM, PHASMD, CC 4.7µF 24.9k CLKOUT, EXTVCC, SGEN, DGEN DRVSET DTC VIN OPERATES THROUGH TRANSIENTS UP TO 75V. DRVUV FREQ GND TMR WHEN VIN > 24V, VOUT FOLLOWS VIN UP TO 57V. 1nF Rev. A 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 Typical Application Related Parts
FEATURES DESCRIPTION
n
Input Supply Range: 4.5V to 65V (Up to 75V Surge)
The LTC®3897 is a synchronous boost DC/DC controller n
Reverse Input Protection to –40V
with surge stopper and ideal diode controller. n
In-Rush Current Control, Overcurrent Protection
The boost controller drives two N-channel power MOSFET
and Output Disconnect for Boost Converter
stages out-of-phase to reduce input and output capacitor n
Input Voltage Surge Protection with Adjustable
requirements, allowing the use of smaller inductors than
Clamp Voltage
the single-phase equivalent. Synchronous rectification n
Onboard Ideal Diode Controller
reduces power loss and eases thermal requirements. n
Low Quiescent Current: 55µA
n
2-Phase Operation Reduces Required Input and
The surge stopper controls the gate of an external
Output Capacitance and Noise
N-channel MOSFET to protect against high voltage input n
Output Voltage Up to 60V
transients and provides in-rush current control, over- n
Adjustable Gate Drive Level 5V to 10V (OPTI-DRIVE)
current protection and output disconnect for the boost
for Logic-Level or Standard Threshold FETs
converter. The integrated ideal diode controller drives n
No External Bootstrap Diodes Required
another N-channel MOSFET to replace a Schottky diode for reverse input protection and voltage holdup or peak detection. It controls the forward voltage drop across the
APPLICATIONS
MOSFET and minimizes reverse current flow. n Industrial The LTC3897 is available in thermally-enhanced 38-pin n Automotive leadless QFN or 38-lead TSSOP packages. n Military/Avionics All registered trademarks and trademarks are the property of their respective owners. Protected by U.S. patents, including 5408150, 5481178, 5705919, 5929620, 6144194, 6177787, 6580258.
TYPICAL APPLICATION 24V/10A 2-Phase Synchronous Boost Converter with Surge Protection and Reverse Protection Efficiency and Power Loss
REVERSE CURRENT PROTECTION (IDEAL DIODE)
vs Output Current
INPUT VOLTAGE SURGE PROTECTION 5mΩ 3.5µH REVERSE INPUT VOLTAGE PROTECTION IN-RUSH/OVERCURRENT PROTECTION 100 100k BURST EFFICIENCY V 90 IN 2mΩ VBIAS SENSE1+ 6V TO 80 10k 55V 33µF 549k SENSE1– POWER LOSS (mW) 70 SPFB BG1 0.1µF 10Ω 60 1k 12.1k BURST LOSS BOOST1 50 10nF IS– SW1 40 100 IS+ TG1 EFFICIENCY (%) 30 DG 5mΩ 3.5µH VOUT V 24V IN = 12V CS SENSE2+ 20 V 10 10A OUT = 24V SG LTC3897 SENSE2– 10 Burst Mode OPERATION V FIGURE 17 CIRCUIT IN BG2 220µF 0.1µF RUN 0.1µF 0 1 0.001 0.01 0.1 1 10 SS BOOST2 OUTPUT CURRENT (A) 15nF 3897 TA01b 8.66k SW2 ITH 1µF TG2 475k INTV PINS NOT SHOWN IN THIS CIRCUIT: CC VFB PLLIN/MODE, I DRV 3897 TA01a LIM, PHASMD, CC 4.7µF 24.9k CLKOUT, EXTVCC, SGEN, DGEN DRVSET DTC VIN OPERATES THROUGH TRANSIENTS UP TO 75V. DRVUV FREQ GND TMR WHEN VIN > 24V, VOUT FOLLOWS VIN UP TO 57V. 1nF Rev. A 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 Typical Application Related Parts
