Datasheet LT8618, LT8618-3.3 (Analog Devices)

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