Datasheet

simultaneously.
To achieve a larger maximum load, the user can either increase the input power supply voltage or increase the
transformer turns ratio properly. Refer to the MAX256 data sheet for details. The power efficiencies are illustrated in
Figure 2 and Figure 3.
For asymmetrical voltage level applications, the maximum load can be larger for one rail and less for the other rail.
Figure 2. Power efficiency vs. current load for ±12V
outputs.
Figure 3. Power efficiency vs. current load for ±15V
outputs.
The output noise is well below 0.5% of the output voltages. The noise is mainly due to the switching pulses of the
MAX256. Figure 4 and Figure 5 display the noise at no load for 12V and 15V outputs, respectively. Figure 6 and
Figure 7 display the noise at the maximum loads for 12V and 15V outputs, respectively.
The noise on the negative rails is identical to the positive rails for symmetrical load applications.
Figure 4. Noise at VOUT = 12V, IOUT = 0mA. Figure 5. Noise at VOUT = 15V, IOUT = 0mA.
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