MM145453_00 NSC [National Semiconductor], MM145453_00 Datasheet - Page 4

• Manufacturer Part Number: MM145453_00
• Description: Liquid Crystal Display Driver
• Manufacturer: NSC [National Semiconductor]

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Applications Information
A R
value of 0.01µF and a V
typical oscillator frequency ( f
f
BP_OUT pin. For this example the approximate BP_OUT
frequency will be f
The BP_IN pin of the MM145453 can be used with an
externally supplied signal, provided it has a duty cycle of
50%. Any deviation from a precise 50% duty cycle will result
Input Data Format
OSC
OSC_IN
signal is divided by 16 before it is presented at the
resistor value of 50kΩ with a C
OSC
/16, or about 75Hz.
DD
value of 5.00V would produce a
OSC
) of about 1200Hz. The
OSC_IN
(Continued)
capacitor
FIGURE 3.
4
in an offset voltage on the LCD. The use of an external clock
allows synchronizing the display drive with AC power, other
internal clocks, or DVM integration time to reduce interfer-
ence from the display. When using an external clock for the
back plane drive the internal oscillator should be disabled by
connecting the OSC_IN pin directly to ground. This will
prevent possible internal oscillations, and reduce device dis-
sipation.
The MM145453 is a pin out variation of the MM5453. For
additional applications information please refer to the
MM5453 data sheet.
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