A6120
AiT Semiconductor Inc.
www.ait-ic.com
LOW DROPOUT VOLTAGE REGULATOR
2A LOW CONSUMPTION LINEAR REGULATOR
TYPICAL APPLICATION
A6120 has fixed voltage and adjustable voltage application mode.
A 1μF ceramic capacitor connected between input and GND as bypass capacitor and a 1μF ceramic capacitor
between output and GND are recommended for all application.
Using a bypass capacitor (CADJ) between the adjust terminal and ground can improve ripple rejection. The
bypass capacitor prevents ripple from being amplified in case the output voltage is increased. The impedance
of CADJ should be less than the resistance of R1 to prevent ripple from being amplified at any frequency. As R1
is normally in the range of 1kΩ~10kΩ, the value of CADJ should satisfy the following condition:
1/(2π* FrequencyRipple *CADJ)<R1
A 0.1μF ceramic capacitor is recommended.
Fig 2. Typical Application of A6120
EXPLANATION
The output voltage of adjustable application satisfies this followed equation:
VOUT=VREF× (1+R2/R1)+IADJ×R2.
The second term IADJ×R2 can be ignored since the adjustable pin current IADJ (~ 2μA) is much less than the
current through R1 (~1mA).
The value of R1 is preferred in the range of 1kΩ~10kΩ and the value of VREF is the output voltage of typical
fixed voltage application circuit.
REV2.2
- DEC 2013 RELEASED, JUL 2017 UPDATED -
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