View QPO-1-EVAL3_1299991.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

P R E L I M I N A RY
QuietPower TM
QPO-1-EVAL3
QPO-1 Evaluation Board, Micro Foot Print DC-DC Converters
Description
The QPO-1-EVAL3 is designed to allow full testing of the QPO-1 and its various performance settings to optimize final system design. The board offers switch settings for the user to select preset values for the Rhr, Rsc, and Rsa resistors. Solder pads are available to mount user-selected values of these components if required. Please refer to the QPO-1 product data sheet, and the following pages for the proper application of this board. The EVAL3 accommodates Vicor's quarter brick DC-DC converters with an input up to 72 Vdc. The QPO-1 output ripple attenuator SiP uses active filtering to reduce output ripple and noise (PARD) over 20 dB from 50 Hz to 500 kHz. The QPO-1 operates over a voltage range from 3 to 30 Vdc and supports load currents as high as 10A. Output regulation is maintained with remote sense or trim adjustment of the power supply. The closed loop architecture improves transient response and ensures precise point-of-load regulation. Other eval boards (see part numbering description) allow easy evaluation with other DC-DC converters or power supplies with standard terminations.
Features of the QPO-1
* >30 dB PARD attenuation, 1 kHz to 500 kHz * >20 dB PARD attenuation, 50 Hz to 500 Hz 1 * 10A rating over a 3-30 Vdc operating range * Supports precise point-of load regulation * Up to 99% efficiency with power limit protection * User selectable optimization of attenuation, power dissipation & transient load response * Peak detector function optimizes for ripple amplitude variation automatically * 1.0 x 1.0 x 0.2" SiP with BGA or LGA mounting * 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 the REFGND pin.
Typical Application
QPO-1 Performance
LOAD+ VOUT+ SENSE+ QPO-1 SC
SC REFGND SC SET CESR VREF QPO IN QPO OUT
QPO IN (AC)
Rsc Cout
GND
QPO OUT (AC)
Rhr
SENSEVOUT-
LOAD-
LOAD CURRENT (DC) 1A/DIV
Figure 1 - SC/Trim supports applications that don't require remote sense. Picor Corporation * www.picorpower.com
Figure 2 - Typical performance with a 3.3 Volt converter. QPO-1-EVAL3 Data Sheet Rev. 1.1 Page 1 of 4
P R E L I M I N A RY
PICOR QPO-1
3V to 30V Input Voltage
Micro Application Board rev.2
Optional Transient Capacitors
C6
C7
External Load 10A Maximum
QPO IN
QPO OUT
LOADLOAD+
1
7
GND
2
C5
SC
QPO-1
ENGINEERING SAMPLE
US AND FOREIGN PATENTS, PATENTS PENDING
6
R1 COUT
3
O N
12
SW2
PHIL
QPO-1
XXXXA
R8 R7
4
5
Input Supply
Supply+ SupplyEarth
+
SW3
R6
SW1 O N
1
2
3
EARTH/Baseplate
VREF
Slope Adjust Bypass
UP DOWN SW2: SC Function 1: SC Capacitor IN OUT 2: SC Control Enabled Disabled
C8
12V 5V 3.3V 28V = All Off
Figure 3 - EVAL3 Board layout and measurement locations.
QPO IN QPO IN QPO IN SupplyC1 MH1 4.7nF Input Supply 3 2 1 C5 100uF
MICRO1 MICRO FOOTPRINT
QPO OUT QPO OUT QPO OUT
BasePlate MH2 MH3
C2 18 4.7nF R11 TBD 11 12 13 14 15 6 3 SW2B
QPO IN QPO IN QPO IN QPO IN PEAK IN SC GND GND GND SLOPE ADJ
17
QPO OUT
QPO IN
SC 2 204-2ST SW2A 1 204-2ST C10 3.3uF C9 TBD
QPO OUT QPO OUT QPO OUT QPO OUT SC SET CESR REFGND VREF
4
5
10 9 8 7 6 5 CESR SC SET COUT 15uF GND
3
16 19
2
1
7
4 SC
20
QPO-1 RAM SIP REV1H
1
2
3
MH6
MH5
C3 Supply+ 4.7nF
MH4
C4 4.7nF
R6 optional 3 C6 270uF C7 270uF 1
BasePlate
4
SW3 CAS-120B1 2
R7 user defined
VREF QPO OUT R8 86.6K 12 11 R3 9.76K R9 35.7K 10 9 R4 4.02K R10 23.7K 8 7 R5 2.67K C8 optional VREF
SW1A 204-213ST 1 2
SW1B 204-213ST 3 4
SW1C 204-213ST 5 6
VREF 12V 5V 3.3V
SC SET
Figure 4 - Schematic of EVAL3 Picor Corporation * www.picorpower.com QPO-1-EVAL3 Data Sheet Rev. 1.1 Page 2 of 4
+
R10 R3 R5 R4 R9
+
R11
C9
C10
R1 user defined
2 1 External Load
P R E L I M I N A RY
Switch Tables
The QPO-EVAL3 board has been designed to accommodate a wide range of output voltages from a micro footprint DC-DC converter. Switch 1 (SW1 in the lower-right corner of the pc board) is used to set the appropriate headroom voltage and SC current for converters with 12V, 5V or 3.3 Vdc outputs. Optimal headroom and SC current settings are pre-defined and the appropriate components are populated on the board. The board EVAL3 will also accommodate user defined output voltages. With all SW1 switches in the "down" position (open circuit), the switch settings allow access to the open pads for R1 and R7. The user must calculate a value for headroom voltage setting resistor (R7) and the SC current setting resistor (R1) and populate the pads with the selected components. Originally, this position was designed to be used with a 28V converter, hence the reference to "28V - ALL OFF" on the pc board. With the first switch of SW1 in the "up" position, and the rest in the "down" position, the headroom voltage and SC current setting is adjusted to work with a 12V converter. With the second switch of SW1 in the "up" position, the rest "down", the converter is set to work with a 5V converter. With the third switch "up", the rest "down", the board is set to work with a 3.3V converter. This switching network will parallel the switched in resistors with R7 and R1. If a predefined voltage is to be used, R7 and R1 should not be populated. At no time should more than one switch be in the "up" position to get accurate results. SW2 is used to engage the SC control function and to add an additional bypass capacitor to the SC pin of the converter. With the first switch of SW2 in the "up" position, a 3.3uF capacitor (C10) is added to the SC pin of the converter. With the second switch of SW2 in the "up" position, the SC control circuit of the QPO is connected to the converter. When the switches are in the "down" position, the capacitor and SC connection are opened and out of the circuit. SW3 is used to engage the optional Slope Adjust resistor when in the "up" position.
Instructions For Use
The terminal block in the lower left-hand corner of the pc board (labeled "Input Supply") is used to provide the input voltage to the DC-DC converter. The output load should be connected to the terminal block on the right, labeled "External Load" and should not exceed 10 Amps. The QPO application board has Johnson Jacks mounted on three key measurement points. These jacks greatly reduce the amount of radiated noise that gets picked up by the ground clip leads of the scope probes. QPO IN is the input to the QPO from the DC-DC converter. QPO OUT is the output of the QPO where effects of the various settings can be analyzed. VREF is the reference voltage that the QPO uses to maintain a desired output voltage. A resistor from this pin to ground will determine the QPO's operating headroom voltage (the voltage drop between QPO IN and QPO OUT) according to the following equation:
Rhr =
QPOout * 2.5k Vhr
where; Rhr is headroom resistor value, QPOout is the voltage seen on the QPO's output, Vhr is the target headroom voltage. The Rsc resistor is tied between QPOOUT and SC SET pin and sets the correction current used to trim up the converter to maintain a constant output voltage on the QPO's output. The value for the SC SET resistor is calculated by the following equation:
Rsc =
Rin * Vout Vrpt
where; Rsc is SC SET resistor value, Rin is the input resistance of the SC or TRIM, Vout is the source output voltage, Vrpt is the pre-trimmed reference of the SC or TRIM. On the application board there are two spots for additional capacitors (C6 and C7) to be added to the QPO's input. These might be required if higher transient steps are needed from higher output voltage converters. These converters typically have lower output capacitance than lower output voltage converters do.
Picor Corporation * www.picorpower.com
QPO-1-EVAL3 Data Sheet Rev. 1.1 Page 3 of 4
R11 and C9 are used for filtering the input to the QPO's peak detector input. The QPO's peak detector circuit will increase the headroom of the QPO by roughly half of the peak-to-peak ripple on the QPO's input. At low input voltage, the added headroom might cause the SC circuit to trim up a converter to a point where it shuts down due to an over-voltage fault. There is a spot for adding an addition capacitor to VREF (C8) if greater attenuation is needed at lower frequencies.
Ordering Information
Part Number QPO-1-EVAL3 Description Evaluation board for QPO-1 for Micro footprint DC-DC Converters
Vicor's comprehensive line of power solutions includes high-density AC-DC & DC-DC modules and accessory components, fully configurable AC-DC & DC-DC power supplies, and complete custom power systems.
Information furnished by Vicor is believed to be accurate and reliable. However, no responsibility is assumed by Vicor for its use. No license is granted by implication or otherwise under any patent or patent rights of Vicor. Vicor components are not designed to be used in applications, such as life support systems, wherein a failure or malfunction could result in injury or death. All sales are subject to Vicor's Terms and Conditions of Sale, which are available upon request.
Specifications are subject to change without notice.
Vicor Corporation 25 Frontage Road, Andover, MA, USA 01810 Tel: 800-735-6200 Fax: 978-475-6715
Email Vicor Express: vicorexp@vicr.com Technical Support: apps@vicr.com
Picor Corporation * www.picorpower.com * QPO-1-EVAL3 Data Sheet
P/N 27091
Rev. 1.1
9/03/10M

▲Up To Search▲

Price & Availability of QPO-1-EVAL3

	To Download QPO-1-EVAL3 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .