NJU6624C New Japan Radio, NJU6624C Datasheet - Page 19

• Manufacturer Part Number: NJU6624C
• Description: 14-CHARACTER 1-LINE DOT MATRIX LCD CONTROLLER DRIVER with SMOOTH SCROLL FUNCTION
• Manufacturer: New Japan Radio

( ( 5)LCD display
(5-1)Bleeder Resistance
(5-1)Bleeder Resistance
(5-2)Relation between oscillation frequency and LCD frame frequency
(5-2)Relation between oscillation frequency and LCD frame frequency
5)LCD display
Each LCD driving voltage ( V
Each LCD driving voltage ( V
the E.V.R. and high impedance bleeder resistance.
the E.V.R. and high impedance bleeder resistance.
The bleeder resistance is set 1/4 bias suitable for 1/8 duty ratio.
The bleeder resistance is set 1/4 bias suitable for 1/8 duty ratio.
The capacitor connected between VLCD2 and V
The capacitor connected between VLCD2 and V
capacitance requires to operate with the LCD panel actually.
capacitance requires to operate with the LCD panel actually.
As the NJU6624C incorporate oscillation capacitor and resistor for CR oscillation, 145kHz oscillation is available
As the NJU6624C incorporate oscillation capacitor and resistor for CR oscillation, 145kHz oscillation is available
without any external components.
without any external components.
The LCD frame frequency example mentioned below is based on 145kHz oscillation.(1clock =6.90us)
The LCD frame frequency example mentioned below is based on 145kHz oscillation.(1clock =6.90us)
COM1
COM1
VLCD
VLCD
VSS
VSS
V4
V4
V1
V1
V2
V2
VLCD2
VLCD2
VLCD1
VLCD1
VSS
VSS
V1
V1
V2
V2
V4
V4
2 2 4 c l o c k s
I c o n
1 frame = 6.90(us) x 224 x 8 = 12.36(ms)
1 frame = 6.90(us) x 224 x 8 = 12.36(ms)
Frame frequency = 1 / 12.36(ms) = 79.50(Hz)
Frame frequency = 1 / 12.36(ms) = 79.50(Hz)
Key scan time = 220.70(uS)
Key scan time = 220.70(uS)
V V
1
LCD
LCD
P o w e r
s u p p l y
1 1
+
, V
, V
2
is the maximum amplitude for LCD driving voltage.
is the maximum amplitude for LCD driving voltage.
2 2
, V
, V
+
LCD Driving Voltage vs Duty Ratio
LCD Driving Voltage vs Duty Ratio
3
1 f r a m e
V
3 3
, V
, V
+
Duty Ratio
LCD
4 4
..............
Bias
+
) is
) is LCD driving high voltage input to the VLCD1 terminal,
LCD driving high voltage input to the VLCD1 terminal, generated by
SS
SS
7
is needed for stabilizing VLCD. The determination of the each
is needed for stabilizing VLCD. The determination of the each
4K
4K
4K
4K
4K
4K
4K
4K
E.V.R.(16Step)
E.V.R.(16Step)
5K
5K
K e y
Internal NJU6624
Internal NJU6624
I c o n
V L C D 2 - V S S
1/8
1/4
1
2
VLCD
VLCD
V2
V2 (V3)
VSS
VSS
V4
V4
V1
V1
3
1 f r a m e
(V3)
..............
NJU6624C
NJU6624C
VLCD
VLCD
7
K e y
generated by
I c o n
1
2