QPO-2L Datasheet, PDF (1/12 Pages) Vicor Corporation – QPO-2L Low Voltage Output Ripple Attenuator

®
QPO-2L
QuietPower^™
QPO-2L Low Voltage Output Ripple Attenuator
Description
The QPO-2 output ripple attenuator SiP uses active
filtering to reduce supply output ripple and noise
(PARD) by over 30dB from 1kHz to 500kHz. The
QPO-2 is biased through the VAUX input and filters
an input voltage range of 0.3VDC to 5.5VDC while
supporting load currents as high as 20A. The VAUX
input range is 7V to 12V with a minimum required
difference between VAUX and QPO OUT of 7V.
Output regulation is maintained by using either the
remote sense or the trim adjustment of the power
supply. The product can be used in an open loop
configuration when ripple and noise reduction are
the main objective and load regulation is not as
critical. The QPO-2 architecture improves transient
response and ensures quiet point-of-load regulation
when used with most switching power supplies. The
performance waveform in figure 2 is an example of
the ripple reduction and transient load
improvement the QPO-2 can provide using a 3.3V
brick style converter.
Applications
• Distributed Point of Load Power Systems
• Sensors Requiring Low Noise Power
• Medical Instrumentation
Typical Application
VOUT+
CIN*
SENSE+
RSL
+TRIM
VAUX
QPO IN
PEAK IN
VAUX
QPO OUT
RCP
QPO-2L
Rsc
RCLAMP
ADJUST
SC SET
LOAD+
Features of the QPO-2
• >30 dB PARD attenuation, 1kHz to 500kHz
• >20 dB PARD attenuation, 50Hz to 500Hz (1)
• 20A rating over a 0.3-5.5Vdc operating range
• Supports precise point-of load regulation
• 90-95% efficiency with load vs. headroom trim
• User selectable performance optimization of the
attenuation, power dissipation & transient load
response
• Peak detector function optimizes headroom for
ripple amplitude variation automatically
• 25 x 25 x 4.5 mm SiP with LGA mounting
• Closed loop control improves transient response
of most DC/DC converters and power supplies
• Reduces required number of output capacitors to
support dynamic loads.
• Patents Pending
Note 1: For off-line supplies 20dB attenuation can be achieved
down to 50Hz with additional capacitance added from the VREF
pin to REFGND.
QPO-2 Performance
QPO IN (AC)
QPO OUT (AC)
CSC
RSA
SENSE-
VOUT-
*Optional
RHR
LOAD-
Figure 1 – ADJUST/Trim supports applications that don’t
require remote sense.
Picor Corporation • www.picorpower.com
LOAD CURRENT
Figure 2 – Typical performance with a 3.3 Volt converter,
showing 1 to 10 A load step.
QPO-2L Data Sheet Rev. 1.1 Page 1 of 12