Cirrus Logic is a newcomer to the LED driver IC market, but the company claims it will make an immediate impact asserting that a tier-1 lighting vendor will shortly ship a high-volume, retrofit-lamp product based on the new CS161X IC. The company says that it has tested the 2-stage CS161X solid-state lighting (SSL) driver IC with more than 200 triac dimmers and that the IC delivers smooth, flicker-free dimming down to below 2% of maximum output current.

Cirrus targets dimmable retrofit lamps with the CS161X

Cirrus has taken a similar path to Marvell and iWatt in recently-launched dimmers – attempting to recognize the characteristics of the connected dimmer and then selecting an optimal operating mode for that dimmer. Cirrus describes its approach to dimming as a digital implementation in a mixed-signal IC, but evidently the IC is not based on a programmable processor core such as Marvell uses.

The company calls the implementation TruDim Technology. The data sheet describes a dimmer switch detection algorithm that can place the IC in leading- or trailing-edge operating modes. Moreover, once the driver IC is in full operation, the IC performs a dimmer validate function that periodically ensures that the mode selection is still accurate.