Datasheet LT8618, LT8618-3.3 (Analog Devices)
| Manufacturer | Analog Devices |
| Description | High Efficiency 65V/100mA Synchronous Buck |
| Pages / Page | 20 / 1 — FEATURES. DESCRIPTION. High Efficiency Synchronous Operation. > 90% … |
| File Format / Size | PDF / 2.9 Mb |
| Document Language | English |
FEATURES. DESCRIPTION. High Efficiency Synchronous Operation. > 90% Efficiency at 30mA, 12VIN to 3.3VOUT
Model Line for this Datasheet
- LT8618EDDB#TRMPBF LT8618EDDB#TRPBF LT8618EDDB#WTRMPBF LT8618EDDB#WTRPBF LT8618EDDB-3.3#TRMPBF LT8618EDDB-3.3#TRPBF LT8618EDDB-3.3#WTRMPBF LT8618EDDB-3.3#WTRPBF LT8618IDDB#TRMPBF LT8618IDDB#TRPBF LT8618IDDB#WTRMPBF LT8618IDDB#WTRPBF LT8618IDDB-3.3#TRMPBF LT8618IDDB-3.3#TRPBF LT8618IDDB-3.3#WTRMPBF LT8618IDDB-3.3#WTRPBF
Text Version of Document
LT8618/LT8618-3.3 High Efficiency 65V/100mA Synchronous Buck
FEATURES DESCRIPTION
n
High Efficiency Synchronous Operation
The LT®8618 is a compact, high speed synchronous n
> 90% Efficiency at 30mA, 12VIN to 3.3VOUT
monolithic step-down switching regulator that delivers n
Ultralow Quiescent Current Burst Mode® Operation
up to 100mA with high efficiency at constant switching n
< 2.5µA IQ Regulating 48VIN to 3.3VOUT
frequency, even up to 2.2MHz. It accepts a wide input volt- n
Output Ripple < 10mVP-P
age range up to 65V (transients only, 60V for continuous n
3.4V to 60V Input Operation Range (65V Max)
operation), and consumes only 2.5µA of quiescent cur- n
Fast Minimum Switch-On Time: 35ns
rent. Top and bottom power switches are included with n
Adjustable Switching Frequency: 200kHz to 2.2MHz
all necessary circuitry to minimize the need for external n
Fixed 3.3V Output Voltage Version
components. Low ripple Burst Mode operation enables n Allows Tiny Inductors high efficiency down to very low output currents while n Accurate 1V Enable Pin Threshold keeping the output ripple below 10mVP-P. Additional fea- n Internal Compensation tures provide for flexible and robust operation. Internal n Output Soft-Start and Tracking compensation with peak current mode topology allows n Small 10-Lead 3mm × 2mm DFN the use of small inductors and results in fast transient n AEC-Q100 Qualification in Progress response and good loop stability. The EN/UV pin has an accurate 1V threshold and can be used to program VIN under voltage lockout or to shut down the LT8618 reduc-
APPLICATIONS
ing the input supply current to 1µA. If there are no fault conditions, a PG flag signals when VOUT is within ±7.5% n Industrial Sensors of the programmed output voltage. Thermal shutdown n Industrial Internet of Things provides additional protection. The LT8618 is available in n 4mA to 20mA Current Loops a small 10-Lead 3mm × 2mm DFN package with exposed n Flow Meters pad for low thermal resistance. n Automotive Housekeeping Supplies All registered trademarks and trademarks are the property of their respective owners.
TYPICAL APPLICATION 3.3V, Step-Down Converter Efficiency at VOUT = 3.3V
100 VIN VIN 4.2V TO 60V BST 95 1µF VIN = 12V LT8618-3.3 47nF 90 120µH VOUT 85 VIN = 24V OFF ON EN/UV SW 3.3V 1µF 100mA 80 VIN = 48V INTVCC BIAS 10nF 75 TR/SS PG 70 EFFICIENCY (%) 65 RT OUT 60 110k GND 22µF 55 8618 TA1a fSW = 400kHz f 50 SW = 400kHz 0 10 20 30 40 50 60 70 80 90 100 OUTPUT CURRENT (mA) 8618 TA1b Rev. 0 Document Feedback For more information www.analog.com 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Typical Application Related Parts
FEATURES DESCRIPTION
n
High Efficiency Synchronous Operation
The LT®8618 is a compact, high speed synchronous n
> 90% Efficiency at 30mA, 12VIN to 3.3VOUT
monolithic step-down switching regulator that delivers n
Ultralow Quiescent Current Burst Mode® Operation
up to 100mA with high efficiency at constant switching n
< 2.5µA IQ Regulating 48VIN to 3.3VOUT
frequency, even up to 2.2MHz. It accepts a wide input volt- n
Output Ripple < 10mVP-P
age range up to 65V (transients only, 60V for continuous n
3.4V to 60V Input Operation Range (65V Max)
operation), and consumes only 2.5µA of quiescent cur- n
Fast Minimum Switch-On Time: 35ns
rent. Top and bottom power switches are included with n
Adjustable Switching Frequency: 200kHz to 2.2MHz
all necessary circuitry to minimize the need for external n
Fixed 3.3V Output Voltage Version
components. Low ripple Burst Mode operation enables n Allows Tiny Inductors high efficiency down to very low output currents while n Accurate 1V Enable Pin Threshold keeping the output ripple below 10mVP-P. Additional fea- n Internal Compensation tures provide for flexible and robust operation. Internal n Output Soft-Start and Tracking compensation with peak current mode topology allows n Small 10-Lead 3mm × 2mm DFN the use of small inductors and results in fast transient n AEC-Q100 Qualification in Progress response and good loop stability. The EN/UV pin has an accurate 1V threshold and can be used to program VIN under voltage lockout or to shut down the LT8618 reduc-
APPLICATIONS
ing the input supply current to 1µA. If there are no fault conditions, a PG flag signals when VOUT is within ±7.5% n Industrial Sensors of the programmed output voltage. Thermal shutdown n Industrial Internet of Things provides additional protection. The LT8618 is available in n 4mA to 20mA Current Loops a small 10-Lead 3mm × 2mm DFN package with exposed n Flow Meters pad for low thermal resistance. n Automotive Housekeeping Supplies All registered trademarks and trademarks are the property of their respective owners.
TYPICAL APPLICATION 3.3V, Step-Down Converter Efficiency at VOUT = 3.3V
100 VIN VIN 4.2V TO 60V BST 95 1µF VIN = 12V LT8618-3.3 47nF 90 120µH VOUT 85 VIN = 24V OFF ON EN/UV SW 3.3V 1µF 100mA 80 VIN = 48V INTVCC BIAS 10nF 75 TR/SS PG 70 EFFICIENCY (%) 65 RT OUT 60 110k GND 22µF 55 8618 TA1a fSW = 400kHz f 50 SW = 400kHz 0 10 20 30 40 50 60 70 80 90 100 OUTPUT CURRENT (mA) 8618 TA1b Rev. 0 Document Feedback For more information www.analog.com 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Typical Application Related Parts
