ACE517C datasheet(6/9 Pages) ACE

6 / 9 page

ACE517C

2A Low Consumption Linear Regulator

VER 1.2

DETAILED DESCRIPTION

ACE517C is a series of low dropout voltage and low power consumption regulator. Its application

circuitry requires minimum number of external components. Both fixed voltage and adjustable voltage

application circuits need input and output capacitors to assure output voltage stability. Any desired output

voltage from fixed voltage to 18V can be achieved by assigning proper values to two external resistors in

its application circuitry (as shown in Fig.3, as R1, R2 are the two external resistors.).

ACE517C uses trimming technique to assure the accuracy of output value within ±2%, at the same time,

temperature compensation is elaborately considered in this chip, which

makes ACE517C’s temperature

coefficient within 100ppm/℃

TYPICAL APPLICATION

ACE517C has fixed voltage and adjustable voltage application mode, Fig.4 shows their typical application

circuitry.

A 1uF ceramic capacitor connected between input and GND as bypass capacitor and a 1uF 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 C

Adj should satisfy the following

condition:

1/(2

* Frequency

Ripple *Cadj)<R1

A 0.1µF ceramic capacitor is recommended.

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.

ACE517C Datasheet(PDF) 6 Page - ACE Technology Co., LTD.