Three new hot-swap managers from Texas Instruments help protect against overcurrents for voltage rails between 3 and 20 V and an operating current of up to 5 A. The TPS2420 comes in a tiny 16-pin quad-flat no-lead (QFN) package, and the TPS2421-1 and TPS2421-2 come in 8-pin small-outline IC (SOIC) packages. All three offer more than twice the current throughput of existing hot-swap managers with integrated FETs in the same voltage range.
The TPS2420 family supports applications such as disk-drive arrays, network clients, industrial monitoring devices, and communications systems. The devices require up to 70% fewer external components than competitive products to implement a complete circuit. Each device can operate across the entire operating voltage range with only the timing capacitor and resistor-set current thresholds.
Among the devices’ key features are an onboard FET RDS(ON) of 20 mO and a fault threshold that’s adjustable from zero to 5 A. The TPS2420 also offers an independent current-limit threshold. The devices provide power limiting with fast overload protection as well as a programmable fault timer.
The devices’ current range enables them to fit many applications. Hot-swap managers are commonly designed into systems that require multiple system-voltage rails. They improve overall system efficiency and eliminate nuisance shutdowns. They’re also useful for system control and to enable downstream dc-dc converters.
The TPS2420 is available now in a QFN-16 package. The TPS2421-1 and TPS2421-2 will be available in the second quarter of 2009 in SOIC 8-pin packages. The TPS2420 costs $1.95 and the TPS2421-1 and TPS2421-2 cost $1.60 in quantities of 1000.