Datasheet LTC4418 (Linear Technology)

LTC4418 Dual Channel Prioritized PowerPath Controller
FEATURES DESCRIPTION
n
Selects Highest Priority Supply from Two Inputs
The LTC®4418 connects one of two valid power supplies n
Blocks Reverse and Cross Conduction Currents
to a common output based on priority and validity. Priority n
Wide Operating Voltage Range: 2.5V to 40V
is defined by pin assignment, with V1 assigned the higher n
–42V Protection Against Reverse Connection
priority and V2 the lower priority. A power supply is defined n
60V Tolerant V1, V2 Inputs
as valid when its voltage has been within its overvoltage n
Adjustable Input Validation Time
(OV) and undervoltage (UV) window continuously for at n Fast Switchover Minimizes Output Voltage Droop least the configured validation time. If the highest priority n Low 26µA Operating Current valid input falls out of the OV/UV window, the channel is n ±1.5% Input Overvoltage/Undervoltage Protection immediately disconnected and the other valid input is con- n Adjustable Overvoltage/Undervoltage Hysteresis nected to the common output. Multiple LTC4418s, as well n Cascadable for Additional Input Supplies as triple channel LTC4417s, can be cascaded to provide n 20-Lead 4mm × 4mm QFN Package switchover between more than two inputs. The LTC4418 incorporates fast non-overlap switching
APPLICATIONS
circuitry to prevent both reverse and cross conduction while minimizing output droop. The gate driver includes n Industrial Handheld Instruments a 6V clamp to protect external MOSFETs. A controlled n High Availability Systems soft-start feature minimizes start-up inrush current. Open n Battery Backup Systems drain VALID outputs indicate the input supplies have been n Servers and Computer Peripherals within their OV/UV window for the duration of the valida- L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and tion time. The validation time can be disabled or adjusted ThinSOT and PowerPath are trademarks of Analog Devices, Inc. All other trademarks are the property of their respective owners. using an external capacitor.
TYPICAL APPLICATION
M1 FDS4465 M2 5V SYS 1.25A MAX OUTPUT + 82µF
Priority Switching from V1 to V2
M3 FDS4465 M4 12V WALL ADAPTER 47nF 13.8V V2 2V/DIV 100nF 470nF 698Ω BAT46WJ VS1 G1 VS2 G2 V V1 OUT V 1M OUT 100k UV1 100k 5V 60.4k VALID1 V1 OV1 2V/DIV VALID2 226k LTC4418 CAS ILOAD = 1.25A C V2 INTV OUT = 82µF CC 1M EN 4418 TA01b UV2 2ms/DIV 33.2k SHDN OV2 GND HYS TMR 78.7k 4418 TA01a 255k 1nF 100nF 4418f For more information www.linear.com/LTC4418 1 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Timing Diagram Operation Applications Information Typical Applications Package Description Typical Application Related Parts