EV1570DN-00A Datasheet, PDF (5/5 Pages) Monolithic Power Systems – 3A, 23V, 340KHz Synchronous Step-Down Converter

EV1570DN-00A – 3A, 23V, 340KHz SYNCHRONOUS STEP-DOWN CONVERTER
EVALUATION BOARD – INITIAL RELEASE
QUICK START GUIDE
1. Connect the positive terminal of the load to VOUT pins, and the negative terminal of the load to
GND pins.
2. Preset power supply output to 4.75V to 23V and turn off the power supply.
3. Connect the positive terminal of the power supply output to VIN pin, and the negative terminal of
the power supply output to GND pin.
4. Turn power supply on and the MP1570 will automatically startup.
5. To use Enable function, apply a digital input to EN pin. Drive EN higher than 2.5V to turn on the
regulator, drive EN less than 0.7V to turn it off.
6. An under voltage lockout (UVLO) function can be implemented by the addition of a resistor
divider R4 and R5. The EN threshold is 2.5V, so VIN UVLO threshold is: ⎜⎛1+ ^R4 ⎟⎞ × 2.5V .
⎝ ^R5 ⎠
RECOMMENDED COMPONENTS FOR STANDARD OUTPUT VOLTAGES
The output voltage of this board is set to 3.3V. This board is laid out to accommodate most commonly
used inductors and output capacitors and to be programmed for most standard output voltages. The
following table lists recommended components for some standard output voltages. Listed
compensation components (R2, C3) values are based on the output capacitor installed on this board.
For other capacitors, refer to the Application Information section of the MP1570 datasheet..
V_OUT
1.8V
2.5V
3.3V
5V
12V
R1
4.75kΩ
10.5kΩ
16.9kΩ
30.9kΩ
88.7kΩ
R2
5.6kΩ
4.7kΩ
5.6kΩ
7.5kΩ
10kΩ
C3
3.3nF
4.7nF
3.3nF
3.3nF
1.2nF
L1
4.7µH
4.7µH to 6.8µH
6.8µH to 10µH
10µH to 15µH
15µH to 22µH
NOTICE: The information in this document is subject to change without notice. Please contact MPS for current specifications.
Users should warrant and guarantee that third party Intellectual Property rights are not infringed upon when integrating MPS
products into any application. MPS will not assume any legal responsibility for any said applications.
EV1570DN-00A Rev. 1.1
www.MonolithicPower.com
5
4/6/2005
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