A7330
DC-DC CONVERTER BUCK (STEP-DOWN)
SENSORLESS CC/CV
AiT Semiconductor Inc.
www.ait-ic.com
Select the proper ratio of the two feedback resistors RFB1 and RFB2 based on the output voltage. Adding a
capacitor in parallel with RFB1 helps the system stability. Typically, use RFB2≈10kΩ and determine RFB1 from
the following equation:
VOUT
0.8V
R
FB1=RFB2
−1
CC Current Setting
A7330 constant current value is set by a resistor connected between the ISET pin and GND. The CC output
current is linearly proportional to the current flowing out of the ISET pin. The voltage at ISET is roughly 1V and
the current gain from ISET to output is roughly 100000 (100mA/1μA). To determine the proper resistor for a
desired current, please refer to figure below.
Output Current vs. RISET
CC Current Line Compensation
When operating at constant current mode, the current limit increase slightly with input voltage. For wide input
voltage applications, a resistor RC may be added to compensate line change and keep output high CC
accuracy, as shown figure below.
REV1.0
- JAN 2016 RELEASED -
- 7 -
AITSEMI [ AiT Semiconductor ]
