Power Electronics / Power Management

Load share controller eliminates 'OR'ing diodes for N+1 redundant supplies

9 May 2001 Power Electronics / Power Management

Linear Technology introduces the LTC4350, a controller that allows the load current to be equally shared among multiple power supplies. By using isolation FETs and very low value sense resistors, it provides overvoltage and reverse current protection without the losses associated with ORing diodes. The LTC4350 isolates the power supply from output failures, provides a status indicator and allows the power supply to be hot-swapped without turning off system power. The part communicates with other devices through a share bus and adjusts the power supply voltage to assure equal load sharing among all the power supplies in high power and high reliability systems such as network servers, telecom and basestation equipment or other distributed power supply applications.

Parallelling power supplies is an economical way to achieve redundancy and increase the power capability whether using with modules or switching regulators. To optimise these systems, the load current must be shared equally. In some cases, a failure in any one supply will require that the others carry the load and the faulty supply be disconnected and replaced. The LTC4350 uses a share bus connected to other LTC4350 circuits to communicate the load current. It then adjusts the power supply voltage through the SENSE+ or feedback node on the power supply to assure that the load current is shared equally. The load share function is combined with a Hot Swat controller to allow a power supply to be inserted or removed.

The LTC4350 can control output voltages from 1,5 to 12 V. Specified for the commercial and industrial temperature ranges, the LTC4350 is available in the 16-pin narrow SSOP package in 1000 piece quantities.

Summary of features

* Load share control for N+1 redundant supplies.

* Allows power supply to be hot-swapped.

* Isolates supply failures from output.

* Eliminates ORing diodes.

* Identifies and localises output low, output high and open-circuit faults.

* Controls output voltages from 1,5 to 12 V.

Insight Memec

(021) 674 4124

Share this article:
Share via emailShare via LinkedInPrint this page

Further reading:

650 W fast recovery diodes
RS Components (SA) Power Electronics / Power Management
Rohm has released its 4th-generation 650 V fast recovery diodes (FRDs), balancing forward voltage and reverse-recovery time for high-power industrial and consumer equipment including air conditioners and electric vehicle charging stations.

Wireless charging IC solution
TRX Electronics Power Electronics / Power Management
The WLC1115 transmitter controller IC is the first highly integrated product of the new WLC family of controllers from Infineon for applications in inductive wireless charging.

Real-time monitoring of solar power stations
Otto Wireless Solutions Power Electronics / Power Management
WLink’s 3G/4G routers remotely monitor and manage power stations in real-time and perform fault diagnosis, power prediction and a daily maintenance routine.

1,5 A LDO linear regulator from TI
Altron Arrow Power Electronics / Power Management
The TPS7A74 from Texas Instruments is a 1,5 A low-dropout linear regulator with programmable soft-start for a wide variety of applications.

eFuse with transient overcurrent blanking timer
RS Components (SA) Power Electronics / Power Management
The TPS25981xx family of eFuses from Texas Instruments is a robust defence against overloads, short circuits, voltage surges and excessive inrush current.

New low-cost 60 W PSU
Vepac Electronics Power Electronics / Power Management
The new VCB60 series of 60 W PSUs from XP Power addresses the need for high-quality easy-to-use power solutions at attractive price points.

New series of high-power pure sine wave inverters
Current Automation Power Electronics / Power Management
The NTS/NTU-2200/3200 series pure sine wave inverters by Meanwell now have the ability to use lithium batteries as well as lead acid as the DC power source.

Fully programmable motor controllers
Altron Arrow Power Electronics / Power Management
The MOTIX IMD70xA programmable motor controllers from Infineon are now available in one package to power the next generation of battery-powered applications.

New power converter family from Traco
Conical Technologies Power Electronics / Power Management
Traco Power has announced the release of their new TMR 12WI converter family featuring isolated 12W DC/DC converter modules with regulated outputs.

Bourns releases new series of power inductors
Electrocomp Power Electronics / Power Management
Constructed with a magnetic-silica coating to the perimeter of the inductor winding to provide effective shielding, these inductors release lower magnetic field radiation compared to non-shielded inductors.