Active Output Ripple Attenuators (QPO Series) 10 and 20 Amp Features 25 mm >30 dB PARD attenuation, 1 kHz to 500 kHz Supports precise point-of-load regulation Up to 99% efficient High density, low profile LGA package Reduces required number of output capacitors 4.5 mm QPO 25 mm US AND FORIEGN PATENTS PENDING •081 PHIL 0315A to support dynamic loads QUIETPOWER™ User selectable optimization of attenuation, power dissipation, and transient load response Compatible with most DC-DC converters Product Description Applications The QPO output ripple attenuator products use proprietary active filtering to reduce power supply output ripple and noise (PARD) over 30 dB from 1 kHz to 500 kHz. QPOs improve transient response, ensures quiet point-of-load regulation and works with most DC-DC converters and switching power supplies. Output regulation is maintained using remote sensing or the trim input of the power supply. Telecom base station power amplifiers Low noise POL Industrial test and measurement Sensors requiring low noise power Medical instrumentation Military targeting and displays Lasers and optical systems Load capacitance using this active technique can effectively be reduced by a factor of 10, providing equivalent transient performance. In the typical application schematic below the QPO was inserted between the converter and the load using no additional load capacitance. As shown in the performance plot, the drop in load voltage (approx. 10 mV; channel 2) was significantly reduced when compared to the converter output (approx. 100 mV; channel 1) with a 10 A transient load current step. The ripple voltage amplitude was also reduced by a similar factor at the load. QPO Evaluation Boards Available For more information, go to picorpower.com Part Numbering Part Number (Z=RoHS) Input Voltage Current Rating Attenuation QPO-1L(Z) 3 – 30 Vdc 10 A >30 dB PARD, 1 kHz to 500 kHz QPO-2L(Z) 0.3 – 5.5 Vdc 20 A >20 dB PARD, 1 kHz to 500 kHz, Aux. Bus bias LOAD+ VOUT+ QPO OUT QPO IN Rsc SENSE+ QPO-1 SC Cout QPO IN (AC) SC SET RSL CESR SC REFGND GND VREF QPO OUT (AC) CSC RHR SENSEVOUTLOAD- Typical Application Defining the Quality of Power Through Innovation LOAD CURRENT (DC) 5A/DIV QPO Performance picorpower.com 800-735-6200 Rev 1.0 11/06 33281