King Billion Electronics Co., Ltd
HE84770
駿 億 電 子 股 份 有 限 公 司
HE80000 SERIES
pump the 2.25 volts to 9 volts requires 4 times multiplier; to pump the 3 volts to 9 volts requires only 3
time multiplier which consumes less power. So it is advisable not to adjust the LVREG to an unnecessary
low level.
Voltage multiplication: The LVREG is then multiplied by 3, 4, or 5 times, depending on external
capacitors configurations as shown below, to generate LVP. Please note that LVP must be lower than 9
volts to prevent chip from breaking down.
x3 multiplier
x4 multiplier
x5 multiplier
4.7uF
LVL1
4.7uF
LVL1
4.7uF
LVL1
0.1uF
LVL2
0.1uF
LVL2
0.1uF
LVL2
0.1uF
LVL3
0.1uF
LVL3
0.1uF
LVL3
4.7uF
LVL4
4.7uF
LVL4
4.7uF
LVL4
10uF
LVL5
10uF
LVL5
10uF
LVL5
LGS2
LGS2
LGS2
R
R
R
4.7uF
LVP
4.7uF
LVP
4.7uF
0.1uF
LVP
LCAP4A
LCAP2B
LCAP2A
LCAP1A
LCAP1B
LCAP3A
LVREG
LGS1
LCAP4A
LCAP2B
LCAP2A
LCAP1A
LCAP1B
LCAP3A
LVREG
LGS1
LCAP4A
LCAP2B
LCAP2A
LCAP1A
LCAP1B
LCAP3A
LVREG
LGS1
0.1uF
0.1uF
0.1uF
0.1uF
0.1uF
0.1uF
0.1uF
0.1uF
0.1uF
0.1uF
0.1uF
0.1uF
R
R
R
LVAG
0.1uF
LVAG
0.1uF
LVAG
The LVP is then regulated to generated LVL1 ~ LVL5. LVL5 can be adjusted by the resistor between
LGS2 and LV5. Be sure to leave at least 0.3 volt between LVP and LV5 for the regulator circuit to
function properly. The formula is:
LVL5 = (1 + R2/80K) x 0.9V
Different duties require different bias settings. There is some theoretical correspondence between the
Duty and Bias Setting. However, it is better to use it as starting point and adjust it with real LCD panel
connected to it to determine the final setting. The theoretic relationship between the duty and bias setting
as following:
Duty Cycle Normal Bias Alternative Bias
32 duty
48 duty
64 duty
80 duty
1/7
1/8
1/7.5
1/7.5, 1/8.5
1/8.5, 1/9.5
1/9.5, 1/10.5
1/9
1/10
The bias setting is made by mask option MO_LBSR[2..0].
MO_LBSR[2..0] Bias Setting
August 25, 2003
Page 13 of 30
V2.6E
This specification is subject to change without notice. Please contact sales person for the latest version before use.
KB [ King blillion Electronics Co.,Ltd. ]
