Current-sharing, diode-OR controller simplifies power system design
June 05, 2012 // Paul Buckley
Claiming a first-of-its-kind current-sharing controller with reverse current blocking, the LTC4370 from Linear Technology frees the designer from the limitations and complications of existing current-sharing methods to obtain a simpler, quicker, and space-saving solution for sharing between two supplies.
The device’s supply-agnostic feature lends the design more flexibility and a longer lifetime. By incorporating diode behavior, the controller prevents one supply failure from bringing down the entire system.
Designers of high availability systems frequently engineer redundancy into their power systems by paralleling two similar supplies with diodes (diode-OR) such that one can handle the load when the other fails. System reliability is further increased if both supplies operate simultaneously, each sharing half the load current. Lower currents lead to cooler operation, reducing the failure rate by half for every 10°C fall in temperature. Other load-sharing benefits include faster recovery after supply failure, and the ability to operate supplies near their peak efficiency point. Prior to the LTC4370, load-sharing solutions demanded active control of the supplies through their trim pins or feedback networks. They also required a share bus, and stability compensation dependent on the supply type. The LTC4370 simplifies designs of reliable power systems.
The LTC4370 controls N-channel MOSFETs in series with each supply. These MOSFETs act like diodes with a variable forward voltage. The LTC4370 adjusts the forward voltage of the MOSFET diodes to offset the mismatch in input supply voltages until the currents from each supply are equal. To limit MOSFET power dissipation, the maximum voltage drop across the MOSFET is adjustable with an external resistor. The controller operates with supplies in the range of 0 V to 18 V. During faults, a fast MOSFET turn-on and turn-off limits the load voltage droop and shoot-through currents between supplies. Enable pins can turn each MOSFET off; when both are off, the controller bias current is lowered. Status pins indicate the MOSFET on state, which can be used to signal a break in current sharing by lighting a red LED. The load sharing feature can also be switched off to turn the device into a dual ideal-diode controller.
Availability and Pricing
Specified over the full commercial and industrial temperature ranges, the LTC4370 is offered in 16-pin DFN (4mm x 3mm) and MSOP packages. Pricing begins at $4.95 each for 1,000-piece quantities and the device is available today in production quantities. Evaluation circuit boards are available online or from your local sales office.
More information LTC4370 current-sharing controller at
Wearable: 'Hardware Ponzi Scheme'
August 31, 2015
If "fitness bands are like hardware Ponzi schemes" where device suppliers must sell more and more new hardware while amusing ...
Keysight expands calibration, asset management services in Europe
Real-time 3D athletes tracking feeds teams with new stats
Intel Investment spotlights drones’ opportunity for chipmakers
MOSFET failure protection for a single output polyPhase converter
Apple joins Pentagon alliance to develop wearable tech
August 28, 2015
The Pentagon (Washington, DC) has announced a Silicon Valley-based manufacturing institute and partnership with a consortium ...
Single material layer process lowers LED manufacturing costs
Aquion Energy forges technology partnership with Eguana Technologies
The route to cleaner e-cars - coupling perovskite solar cells
- Software-Defined Radio Handbook
- Why Making the Move from a Variable Transformer to a VariPLUS is the Right Decision
- Automating Leakage and Functional Testing
- Automotive Circuit Protection using Littelfuse Automotive TVS Diodes
InterviewCEO interview: Ambiq sees broader options for low voltage
Mike Noonen, recently appointed interim CEO at microcontroller startup Ambiq Micro, discusses the focus and opportunities for this pioneering company designing circuits that can operate below the threshold ...
Filter WizardCheck out the Filter Wizard Series of articles by Filter Guru Kendall Castor-Perry which provide invaluable practical Analog Design guidelines.
Linear video channel
READER OFFERRead more
This month, Novelda is giving away two full XeThru Inspiration kits worth 1499 US Dollars each, for EETimes Europe's readers to experiment first hand with its XeThru technology.Based on the use of radio waves, rather than infrared, ultrasound or light, the company's X2M1000 Inspiration modules can detect presence just from the chest movement while breathing, and measure both the rate and... MORE INFO AND LAST MONTH' WINNERS...
December 15, 2011 | Texas instruments | 222901974
Unique Ser/Des technology supports encrypted video and audio content with full duplex bi-directional control channel over a single wire interface.