MOP-AL204A Logic Levels
Posted: Mon Jul 20, 2009 10:00 pm
I am redesigning a micro-controller board for an industrial client that has been using your MOP-AL204A LCD display, which if I understand correctly, uses the S6A0069 LCD controller chip. The micro-controller board that the client was using(obsolete), used 5V logic to drive the display bus. The new design is using 3.3V logic (LVTTL, 5V tolerant) to drive the display bus. In both cases the display supply voltage is 5V. The question is whether or not voltage level translation is needed for the new design on the display bus. Reading the MOP-AL204A specification, the answer seems to be yes (logic high: 0.7x5V=>3.5V); but reading the S6A0069 specification, the answer is no translation needed (logic high: >2.2V).
Which is correct?
MOP-AL204A Specification:
Supply Voltage: 4.5V min., 5.0V typ., 5.5V max.
Input High Voltage: 0.7 Vdd min., Vdd max.
Input Low Voltage: Vss min., 0.3 Vdd max.
S6A0069 Specification:
Supply Voltage: 4.5V min., 5.5V max.
Input High Voltage: 2.2V min., Vdd max. (except OSC1)
Input Low Voltage: -0.3V min., 0.6 V max. (except OSC1)
Supply Voltage: 2.7V min., 4.5V max.
Input High Voltage: 0.7 Vdd min., Vdd max. (except OSC1)
Input Low Voltage: -0.3V min., 0.55 V max. (except OSC1)
Which is correct?
MOP-AL204A Specification:
Supply Voltage: 4.5V min., 5.0V typ., 5.5V max.
Input High Voltage: 0.7 Vdd min., Vdd max.
Input Low Voltage: Vss min., 0.3 Vdd max.
S6A0069 Specification:
Supply Voltage: 4.5V min., 5.5V max.
Input High Voltage: 2.2V min., Vdd max. (except OSC1)
Input Low Voltage: -0.3V min., 0.6 V max. (except OSC1)
Supply Voltage: 2.7V min., 4.5V max.
Input High Voltage: 0.7 Vdd min., Vdd max. (except OSC1)
Input Low Voltage: -0.3V min., 0.55 V max. (except OSC1)