Electronicspecifier, February 2011
Expanding its dual output integrated FET buck regulator range, Intersil has a trio of new devices that provide up to 95% power conversion efficiency for greater flexibility. The new ISL8022, ISL8033/A and ISL8036/A have quiescent currents down to 40µA and support inputs of 2.85~6V, making them ideal for single Li+ cell, three NiMH cell or 3V/5V DC input applications.
These dual output stepdown dc/dc regulators deliver up to 3A/channel continuous output. ISL8022 provides similar functionality for lower current applications, delivering up to 2A/1.7A continuous output current on its two channels. All three device families feature peak current mode, fixed frequency control for ultra-low duty cycle operation, excellent loop stability and fast load transient response. The fast load transient response reduces required output capacitance and enables a smaller total solution size compared with traditional voltage mode control architectures. The two channels in the ISL 8033/A, ISL8036/A and ISL8022 switch 180° out of phase, reducing input ripple current and filtering requirements. Internal loop compensation further reduces the external component count and cost.
ISL8033 and ISL8036 provide 1MHz fixed switching frequency while the ISL8033A and ISL8036A switch at 2.5MHz to significantly reduce overall dc/dc converter size. ISL8033 and ISL8036 can also be synchronised to an up to 6MHz external clock, further reducing overall solution size and eliminating beat frequencies in multiswitcher designs.
Independent enable and PGOOD pins for both channels provide complete start-up control and inherent output monitoring, eliminating the need for discrete sequencers and voltage monitors.
The ISL8033/A and ISL8036/A are offered in a 24 Ld 4mmx4mm QFN package with 1mm maximum height. The ISL8022 is offered in a 4mmx3mm 12 Ld DFN package with 1mm maximum height.
