Press Release Summary:
Housed in SOT-23 package, LTC4412HV diode controller has 2.5-36 V operating range and is suited for use in systems requiring load sharing or automatic switching between DC input power sources. IC regulates gate voltage of external P-channel MOSFET to maintain 20 mV forward voltage drop, and unit provides reverse battery, overcurrent, and MOSFET protection circuitry. Digital control input and open-drain status output pin are provided to interface to microcontroller.
Original Press Release:
Rugged 36V Ideal Diode-OR Operates from -40°C to 125°C
MILPITAS, CA - April 9, 2004 - Linear Technology Corporation introduces the LTC4412HV, a robust "ideal diode" controller with at least 10x lower forward voltage than a Schottky diode. As a result, the device provides increased efficiency by an order of magnitude in systems requiring load sharing or automatic switching between DC input power sources. The LTC4412HV is guaranteed to meet performance specifications from -40°C to 125°C ambient temperature range while the operating voltage range is rated from 2.5V to 36V. The IC regulates the gate voltage of an external P-channel MOSFET to maintain a 20mV forward voltage drop. Compared to a Schottky diode, the LTC4412HV offers the advantages of higher efficiency, less localized heat dissipation and lower dropout voltage. The LTC4412HV provides reverse battery, overcurrent and MOSFET protection circuitry in a tiny SOT-23 package. In addition, it offers a digital control input and an open-drain status output pin to simplify interfacing to a microcontroller. Applications include backup power supplies, multiple-slot battery charger equipment, and multiple-cell Li-Ion battery-powered handheld devices, security systems as well as automotive and industrial systems.
Multiple LTC4412HVs can be connected to allow load sharing with automatic switchover of load between two or more input power sources (e.g.: two batteries and a wall adapter DC input). The status pin (STAT) of the LTC4412HV can be used to enable a second P-channel MOSFET power switch so that both Schottky diodes are eliminated from the diode-OR circuit. The IC's ultra low 11uA quiescent current is independent of the load current. The gate turn-on and turn-off times while driving a 1nF load from a 12V input are 110us and 13us, respectively.
The LTC4412HV is offered in a 6-lead ThinSOT(TM) package (1mm profile SOT-23). The 1,000-piece price starts at $1.70 each.
Summary of Features: LTC4412HV
Very Low Power Loss Replacement for Power Supply ORing Diodes
Minimal External Components (Single Input & Output Capacitors)
Automatic Switching between DC Sources
Simplifies Load Sharing
Status Output Signal Indicates Conducting Input Source
On/Off & Status Control Pin (CTL Pin) for Manual or Microcontroller Interface
Linear Technology Corporation was founded in 1981 as a manufacturer of high performance linear integrated circuits. Linear Technology products include operational, instrumentation and audio amplifiers; voltage regulators, power management devices, DC-DC converters and voltage references; comparators; monolithic filters; communications interface circuits; one-chip data acquisition sub-systems; pulse-width modulators and sample-and-hold devices; and high frequency devices. Applications for Linear Technology's high performance circuits include wireless and broadband telecommunications infrastructure, cellular telephones, networking products and satellite systems, notebook and desk top computers, computer peripherals, video/multimedia, industrial and medical instrumentation, automotive electronics, factory automation, process control, military and space systems, and high-end consumer products including digital cameras, MP3 players and other electronic products.
Note: LT, AND LTC are registered trademarks of Linear Technology Corp.