EM65570
68COM/ 98SEG 65K Color STN LCD Driver
(3) To use the voltage that is boosted four times, place C1 only across CAP1+ and
CAP1-, across CAP2+ and CAP2-, across CAP3+ and CAP1-; and open CAP4+,
CAP2-, CAP5+, & CAP1-
(4) To use the voltage that is boosted five times, place C1 only across CAP1+ and
CAP1-, across CAP2+ and CAP2-, across CAP3+ and CAP1- across CAP4+ and
CAP2-; and open CAP5+ & CAP1-
(5) To use the voltage that is boosted six times, place C1 only across CAP1+ and
CAP1-, across CAP2+ and CAP2-, across CAP3+ and CAP1-, across CAP4+ and
CAP2-, across CAP5+ and CAP1-
When using the built-in booster circuit, output voltage (VOUT) must be less than the
recommended operating voltage (20.0 Volt). If the output voltage (VOUT) is greater
than the recommended operating voltage, normal operation of the chip cannot be
guaranteed.
VOUT=18V
VOUT=9V
VEE=3V
VSS=0V
VEE=3V
VSS=0V
Boosted 3 times
Boosted 6 times
Figure 7-16 Correlation between VEE and VOUT Boost-up Voltages
NOTE
The maximum voltage VOUT of 20V is automatically limited by hardware to avoid
damage to the IC.
7.17 Electronic Volume
The voltage conversion circuit has a built-in electronic volume, which allows VBA to be
controlled with the DV register setting. The relationship between VBA and DV is given
in the following equation:
VBA = (1+ (M+offset)/381) * VREF
Where: M: DV register value
offset: CV register value
VREF: temperature compensation output voltage
The VBA range is from 1.5V to 2V at 25°C.
7.18 Voltage Regulator
The EM65570 has a built-in reference voltage regulator, which generates the voltage
amplified by the input voltage from the internal temperature compensation output
voltage VREF pin. The generated voltage is output at the V0 pin. Even if the boosted
voltage level fluctuates, V0 will remain stable as long as VOUT is higher than V0. A
stable power supply can be obtained using this constant voltage, even if the load
fluctuates. The EM65570 uses the generated V0 level as the reference level of the
electronic volume to generate the LCD drive voltage.
Product Specification (V1.0) 09.05.2005
(This specification is subject to change without further notice)
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ELAN [ ELAN MICROELECTRONICS CORP ]
