Datasheet LT8613 (Analog Devices)

LT8613 42V, 6A Synchronous Step-Down Regulator with Current Sense and 3µA Quiescent Current
FEATURES DESCRIPTION
n
Rail-to-Rail Current Sense Amplifier with Monitor
The LT®8613 is a compact, high efficiency, high speed n
Wide Input Voltage Range: 3.4V to 42V
synchronous monolithic step-down switching regulator n
Ultralow Quiescent Current Burst Mode® Operation:
that consumes only 3µA of quiescent current. Top and n
3μA IQ Regulating 12VIN to 3.3VOUT
bottom power switches are included with all necessary n
Output Ripple < 10mVP-P
circuitry to minimize the need for external components. n
High Efficiency Synchronous Operation:
The built-in current sense amplifier with monitor and con- n
95% Efficiency at 3A, 5VOUT from 12VIN
trol pins allows accurate input or output current regulation n
94% Efficiency at 3A, 3.3VOUT from 12VIN
and limiting. Low ripple Burst Mode operation enables n
Fast Minimum Switch-On Time: 40ns
high efficiency down to very low output currents while n
Low Dropout Under All Conditions: 250mV at 3A
keeping the output ripple below 10mVP-P. A SYNC pin n
Allows Use of Small Inductors
allows synchronization to an external clock. Internal com- n Low EMI pensation with peak current mode topology allows the use n Adjustable and Synchronizable: 200kHz to 2.2MHz of small inductors and results in fast transient response n Current Mode Operation and good loop stability. The EN/UV pin has an accurate n Accurate 1V Enable Pin Threshold 1V threshold and can be used to program VIN undervolt- n Internal Compensation age lockout or to shut down the LT8613 reducing the n Output Soft-Start and Tracking input supply current to 1µA. A capacitor on the TR/SS pin n Small Thermally Enhanced 3mm × 6mm 28-Lead programs the output voltage ramp rate during start-up. QFN Package The PG flag signals when VOUT is within ±9% of the pro- grammed output voltage as well as fault conditions. The
APPLICATIONS
LT8613 is available in a small 28-lead 3mm × 6mm QFN package with exposed pad for low thermal resistance. n Automotive and Industrial Supplies All registered trademarks and trademarks are the property of their respective owners. n General Purpose Step-Down n CCCV Power Supplies
TYPICAL APPLICATION 5V Step-Down Converter with 6A Output Current Limit Efficiency at 5VOUT
100 VIN V V IN = 12V IN BST 5.8V TO 42V 10µF 95 ON OFF EN/UV 0.1µF V 3.9µH 8mΩ V 90 IN = 24V SYNC OUT SW LT8613 5V IMON 1µF 6A 85 ICTRL ISP 80 ISN BIAS EFFICIENCY (%) 75 PG 10pF INTVCC 70 TR/SS 10µF 1M 65 fSW = 700kHz RT FB L = 3.9µH PGND GND 60 1µF 60.4k 243k 100µF 0 1 2 3 4 5 6 LOAD CURRENT (A) 8613 TA01a fSW = 700kHz 8613 TA01b L: EPCOS B82559 Rev. A Document Feedback For more information www.analog.com 1 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Electrical Characteristics Pin Configuration Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Package Description Revision History Typical Application Related Parts