IC family reduces switching regulator output ripple and harmonics by 60-db at high frequencies

February 07, 2012 // By Paul Buckley
Micrel, Inc. has introduced the Ripple Blocker family comprising the MIC94300 voltage follower output and the MIC94310 fixed output, low-dropout (LDO) IC.

The new MIC94300 /MIC94310 were developed to provide more efficient noise suppression for today’s highly sensitive data and image capturing systems.  The MIC94300 integrates a low-RDSon, current-limit switch and a low-pass filter that passes DC and blocks the AC component of the input voltage.  The MIC94310 is a high-performance, low dropout regulator that offers better PSRR performance from DC to 5 Mhz than discrete solutions. 

Both ICs feature an active-high enable pin for power sequencing.  This first-of-a-kind IC family is ideal for today’s most demanding portable applications, including smart phones, medical imaging, tablets/ notebooks/webcams, digital still and video cameras, bar code scanners, GPS and image system processors for image sensors.  

Micrel’s new Ripple Blocker technology improves minimum detectable signal capturing for low-light image sensors by suppressing system power ripple for the Image System Processor (ISP).  By eliminating the large LC filter that would typically be required to reduce ripple in a discrete solution, the MIC943XX series devices provide more usable board space to accommodate space-constrained designs.  In addition, this new series offers an operating input range of 1.8 V to 3.6 V with exceptional transient performance, ultra-low dropout and very high PSRR (80 db @ 1 Khz).

The MIC94300 and the MIC94310 devices deliver up to 200 mA; higher-current devices are under development.  Both ICs offer full current and thermal fault condition protection and the MIC94310 offers ultra-low dropout (17 mV, typical).  The devices also feature a -40 to 125ºC junction temperature range. Package options include 0.88 x 0.88 mm, 4-bump CSP and 1.2 x 1.6 mm Thin-MLF.
The Ripple Blocker family solutions will be previewing at the 2012 APEC Conference, Orlando, Florida, USA,held February 5-9, 2012, booth number 411-413.

Availability and Pricing

The series is currently available in volume, and pricing starts at $0.24 for 1K quantity for the MIC94300 and $0.27 for the MIC94310.  

More information about the MIC943XX evaluation board at