AT1393/A/B/C
Preliminary Product Information
6-Channel DC-DC Converter IC for DSC
Function Description
1. Power Converter
＊Reference voltage block
A temperature independent voltage of typical value at 2.50V is generated from the
power source by the reference voltage circuit, which is used as a reference voltage
for all internal circuitry and supplies load current to external device up to 1 mA.
＊Triangular oscillator block
A triangular oscillation waveform is generated by connecting a timing resistor (RT)
to pin 25 and a timing capacitor (CT) to pin 26. The resulting waveforms CT
(amplitude at 0.3V to 0.8V), CT1 (in phase with CT with amplitude at 1.1V to
1.8V) and CT2 (reverse phase with CT with amplitude at 1.1V to 1.8V) serve as
input to the PWM comparator.
＊Error amplifier block
The error amplifier controls the error signal to the PWM comparator by sensing
the DC/DC converter output voltage. Furthermore, by connecting feedback
resistor and capacitor from the output pin to the inverted input pin of the error
amplifier, an arbitrary loop gain can be set to make the system stable.
＊Inverting amplifier block
The inverting amplifier detects the negative DC/DC converter output voltage
and sends a control signal to the error amplifier.
＊PWM comparator block
The PWM comparator converts the input voltage to pulse width and thereby the
duty cycle of the DC/DC converter.
Channels 1, 2, and 5 main sides, channel 3, 4, and 6 : The comparator keeps the
output transistor turn on while the error
amplifier output voltage and DTC voltage
are higher than the triangular wave voltage.
Channels 1, 2, and 5 synchronous rectification sides : The comparator keeps the
output transistor turn on while the error
amplifier output voltage are lower than the
triangular wave voltage.
2F, No.10, Prosperity RD. II, Science-Based Industrial Park, Hsinchu 300,Taiwan, R.O.C.
Tel: 886-3-563-0878
Fax: 886-3-563-0879
WWW: http://www.aimtron.com.tw
Email: service@aimtron.com.tw
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AIMTRON [ AIMTRON TECHNOLOGY ]
