ACE1117H datasheet(6/11 Pages) ACE

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ACE1117H

1A Bipolar Linear Regulator

VER 1.2

Typical Application

ACE1117H has an adjustable version and six fixed versions (1.2V, 1.8V, 2.5V, 3.3V, 5.0V and 12V)

Fixed output voltage version

ACE1117H

Application circuit of ACE1117H fixed version

1. Recommend using 10uF tan capacitor as bypass capacitor (C1) for all application circuit.

2. Recommend using 10uF tan capacitor to assure circuit stability.

Adjustable Output Voltage Version

ACE1117H provides a 1.25V reference voltage. Any output voltage between 1.25V~12V can be

achievable by choosing two external resistors (schematic is shown below), R1 and R2

ACE1117H-ADJ

Application Circuit of ACE1117H

–ADJ

The output voltage of adjustable version follows the equation: Vout=1.25*(1+R2/R1)+IAdj*R2. We can

ignore IAdj because IAdj (about 50uA) is much less than the current of R1 (about 2~10mA).

1. To meet the minimum load current (>10mA) requirement, R1 is recommended to be 125

Ω or lower. As

ACE1117H-ADJ can keep itself stable at load current about 2mA, R1 is not allowed to be higher than

625

Ω.

2. Using a bypass capacitor (CADJ) between the ADJ pin and ground can improve ripple rejection. This

bypass capacitor prevents ripple from being amplified as the output voltage is increased. The

impedance of CADJ should be less than R1 to prevent ripple from being amplified. As R1 is normally in

the range of 100Ω~500Ω, the value of C

ADJ should satisfy this equation:1/(2

ripple*CADJ)<R1.

ACE1117H Datasheet(PDF) 6 Page - ACE Technology Co., LTD.