AnalogicTech Releases Current-limited Load Switch To Simplify Hot Swap Management
Advanced Analogic Technologies Inc. (AnalogicTech™) announced the AAT4614, a new current-limited P-channel MOSFET power switch for high side load switching applications. Designed to protect peripheral ports from short-circuit and over-voltage events, the new load switch combines reverse current blocking with programmable current limit capability and an integrated fault flag in a silicon footprint up to 30% smaller than traditional implementations.
"While designers of advanced portable systems with hot swap capabilities often need programmability to maximize protection, reverse blocking to control reverse current potentials and a fault flag to indicate over-current or over-temperature conditions, until now they could only add all three functions with a complex discrete approach," said CJ Zhang, Product Line Vice President at AnalogicTech. "By integrating all three features into a single monolithic device, the AAT4614 offers designers the highest level of protection available for hot swap in a simple, seamless solution that requires up to one-third less board space than discrete alternatives."
Operating across an input range of 2.4 to 5.5V, the AAT4614 can be used in both 3 and 5V systems. When the input drops below 2.4V, an under-voltage lockout circuit automatically shuts down operation to avoid saturation.
To protect the device against large input currents which could cause the supply to fall out of regulation, this new load switch features an over current threshold which is programmable up to 1.6A via a resistor from SET to ground. A very fast 1µs current limit transient response reduces the requirements for local supply bypassing.
The AAT4614 adds a reverse current blocking capability to protect the device from reverse current potentials when disabled. In addition, the device features an open drain FAULT flag to indicate an over-current or over-temperature condition. A 4ms blanking time prevents false reporting during charge of a capacitive load.
The AAT4614 also features an RDS(ON) of 130mΩ typical. To conserve power, quiescent current on the AAT4614 is only 10µA. In shutdown mode, supply current decreases to < 1µA. The new switch also features an over-temperature protection circuit that automatically switches the device off if die temperature exceeds a pre-defined limit.
Qualified over a -40 to +85°C temperature range, the AAT4614 is available in a Pb-free 8-pin SC70JW, a 6-pin SOT23 or a 5-pin SOT23 package. It sells for $0.49 in 1K quantities.
