July 24, 2012 – Linear Technology Korea (CEO Hong Sa-kwak) announced the launch of an ultra-compact surge stopper (product name: LTC4364) with integrated ideal diodes that provides low-loss protection, targeting 4V to 80V electronic devices used in automotive, aerospace, and industrial systems. The surge stopper prevents input overvoltage and overcurrent from flowing into electronic devices, enabling continuous operation by overcoming transient surge conditions. The overcurrent limiting function protects the system and power supply from short circuits in the load.
The LTC4364 provides ideal diode control, replacing Schottky diodes in the power path with low-loss N-channel MOSFETs. The ideal diode, featuring robust front-end capabilities, protects the load from reverse inputs as low as -40V and maintains the output voltage during input power outages.
During input voltage surges, such as automotive load dumps, the LTC4364 reduces the excess voltage across the external MOSFET while simultaneously regulating the output to an adjustable safe voltage. This feature enables the use of low-voltage electronic circuits. Similarly, during current surges, the LTC4364 regulates the forward path to the current limit via a sense resistor. In the event of sustained overvoltage or overcurrent, a VDS accelerated timer equipped with an early warning ensures the safe shutdown of the MOSFET.
The LTC4364's wide operating range ensures continued operation even under automotive cold crank conditions, where battery voltage can drop as low as 4V. Equipped with a simple input clamp, this device controls transient surges of over 100V and can withstand -20V applied to the output side. This -20V tolerance is provided by diode blocking and overcurrent limiting functions, making the LTC4364 a perfect solution for protecting output ports. Adjustable input undervoltage and overvoltage thresholds limit startup when voltages are out of range, preventing the battery from being severely discharged and automatically retries into a faulty state. This device can also be used for inrush current control, providing HotSwap™ performance.
The LTC4364 is available in two options. Upon failure, the LTC4364-1 latches off the pass transistor, while the LTC4364-2 implements 0.1% duty cycle automatic retries. Standardized for the full temperature range of commercial, industrial, and automotive applications, the LTC4364 is supplied in 14-pin DFN (4mm x 3mm), 16-pin MSOP, and SO packages. Pricing for this device starts at $3.45 per unit in 1,000-unit quantities and it is currently available for mass production. Evaluation boards are available through local sales offices or online. For more information, please refer to www.linear.com/product/LTC4364 .

Photo Caption: Ideal diode IC-integrated surge stopper withstanding input overvoltage and reverse voltage, and output short circuit and reverse voltage conditions

Product Features: LTC4364
Wide operating range: 4V ~ 80V
Surge resistance of 80V or more when used with a VCC clamp
Adjustable output clamp voltage
Ideal diode that delays output during input power outages
Reverse input protection up to -40V and reverse output protection up to -20V
Overcurrent protection function
Output port protection function
Low 10µA shutdown current at 12V
Adjustable timer that rides through overvoltage faults
0.1% retry duty cycle on failure (LTC4364-2)
14-pin 4mm x 3mm DFN, 16-pin MSOP & SO package