ACE555
400mA LDO Dropout Voltage Regulator
Technology
Detailed Description
ACE555 is a series of low dropout voltage, three terminal regulators. Its application circuit is very simple:
the fixed version only needs two capacitors and the adjustable version only needs two resistors and two
capacitors to work. It is composed of some modules including start-up circuit, bias circuit, bandgap,
thermal shutdown, current limit, power transistors and its driver circuit and so on.
The thermal shut down and current limit modules can assure chip and its application system working
safety when the environment temperature is larger than 140℃ or output current is larger than 600mA.
The bandgap module provides stable reference voltage, whose temperature coefficient is compensated
by careful design considerations. The temperature coefficient is under 100ppm/℃. And the accuracy of
output voltage is guaranteed by trimming technique,
Typical Application
ACE555 has an adjustable version and five fixed versions, Chart1 is its typical application.
ACE555
Vin
Vin
Vout
Vout
GND
+
10uF
+
22uF
Cout
Cin
Application Hints
1.Recommend using 10uF tan capacitor as bypass capacitor(C1) for all application circuit.
2.Recommend using 22uF tan capacitor to assure circuit stability.
3.Using a bypass capacitor(CAdj) between the adjust terminal 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 the resistor’s(R1) which is between output and adjust pins to
prevent ripple from being amplified at any ripple frequency. As R1 is normally in the range of 200Ω~350
Ω,the value of CAdj should satisfy this equation:2*Fripple*CAdj<R1. Recommend using 10uF tan
capacitor.
VER 1.2
4
ACE [ ACE TECHNOLOGY CO., LTD. ]
