Fairchild Semiconductor International (San Jose, CA) announced its first slew-rate control IC, the FDG901D, capable of reducing
current inrush spike voltage and bus disturbances associated with the turning on and off of capacitive loads in battery applications, such as cell phone handsets, PDAs, wireless telephone handsets, portable POS terminals, portable bar code scanners, and palm PCs.
This new device controls the switching rate of an external MOSFET load switch, ensuring a smooth transition between states. The device enables improved operation over a range of MOSFET products while featuring
lower parts count, improved reliability, improved use of circuit-board real estate, lower assembly costs, reduced system costs, extended battery life due to reduced leakage currents, and improved stability of the transition states over time.
The FDG901D controls the turn-on of a p-channel MOSFET to limit inrush current resulting in less power loss and fewer potentially damaging voltage bus transients due to damaging current spikes. During turn-on, the FDG901D slew rate controller drives a p-channel MOSFET's gate using a constant
current source, thus providing an accurate and consistent timing of voltage transition states. The flexible design of this device offers a choice of three programmed dv/dt states, with settings that have a typical gate-drive current of 80µA, 1µA, and 10nA, respectively.
Housed in a small SC70-5 package, the new FDG901D slew rate controller provides all the
functionality of traditional current inrush solutions with none of the drawbacks of currently available solutions.
The price for the FDG901D is $0.29 for 5,000 pieces. Samples and production quantities are available for delivery in eight weeks ARO.
