Triple-output controllers aim for DSL power

Edited by the Electronicstalk editorial team Jun 16, 2004

The ISL6402 and ISL6402A contain two synchronous-buck PWM controllers and a linear regulator in QFN or TSSOP packaging.

The ISL6402 and ISL6402A contain two synchronous-buck PWM controllers and a linear regulator in a small near-chip-scale thermally enhanced 28-pad quad flat no-lead (QFN) package and a 28-lead TSSOP package.

The ISL6402 is efficiency optimised for a wide range of applications, whereas the ISL6402A is designed for xDSL customer premises equipment (CPE) compatibility.

The two PWM convertors in each IC operate 180 degrees out of phase to substantially reduce input ripple voltage, EMI, and total RMS input current.

Both PWMs have independent enable/soft start pins to facilitate power sequencing in the applications.

Operating over a wide 4.5 to 24V supply range, each output is adjustable down to 0.8V.

An internal low dropout linear regulator eliminates the need for an additional 5V bias.

The linear controller uses an external pass transistor to accommodate high output current without dissipating heat inside the IC.

The ISL6402 PWMs switch at 300kHz, which makes them optimal for applications that require multiple low-noise rails and high power efficiency.

The high 1.4MHz switching frequency of the ISL6402A places switching noise above the typical 1.1MHz ADSL band and provides a fast transient response, making it ideal for DSL CPE applications while enabling the use of smaller external components.

Both of these triple regulator ICs incorporate many robust protection features such as adjustable overcurrent protection, hiccup-mode overcurrent protection for output overload/short-circuit conditions and thermal shutdown if the junction temperature exceeds +150C.

The suggested resale price in 100- to 999-unit quantities is $3.00 each for either part in either package.