ml9227 Oki Semiconductor, ml9227 Datasheet - Page 13

• Manufacturer Part Number: ml9227
• Description: 27-bit Duplex/triplex Vfd Controller/driver With Digital Dimming, Adc And Key Scan
• Manufacturer: Oki Semiconductor

FUNCTIONAL DESCRIPTION
Power-on Reset
When power is turned on, ML9227 is initialized by the internal power-on reset circuit.
The status of the internal circuit after initialization is as follows:
• The contents of the shift registers and latches are set to “0”.
• The digital dimming duty cycle is set to “0”.
• All segment outputs are set to Low level.
• GRID1 outputs are set to Low level.
• GRID2 to 3 outputs are set to High level.
• All the ROW outputs are set to Low level.
• INT output is set to Low level.
Mode Data
ML9227 has the seven function modes. The function mode is selected by the mode data (M0 to M2). The relation
between function mode and mode data (M0 to M2) is as follows:
Data Input and Output
Data input and output through the DATA-I/O pin is valid only when the CS pin is set at a High level.
The input data to DATA I/O pin is shifted into the shift register at the rising edge of the serial clock. The data is
automatically loaded to the latches when the CS pin is set at a Low level.
10-bit dimming data (D1 to D10) and 27-bit segment data (S1 to S27) are used for inputting of dimming data and
display data. To transfer these two data, the mode data (M0 to M2) must be sent after each of these data
succeddingly.
The output data from the DATA I/O pin is output from the shift register at the rising edge of the serial clock.
ML9227 outputs 48-bit (6ch × 8bits) A/D data (A11 to A68) and 29-bit key data (S11 to S55, R1 and Q1 to Q3). To
receive these data, the mode data (M0 to M2) must be sent first and then CS must be set once to Low level and set
again to High level.
Then inputting serial clocks, these data are output from the DATA I/O pin.
When the CS pin is set at a Low level, the DATA I/O pin returns to an input pin.
To stop the keyscan, the only mode data (M0 to M2) must be sent. After the mode data transfer, the key scanning is
stopped immediately.
OKI Semiconductor
FUNCTION MODE
0
1
2
3
4
5
6
7
Segment Data for GRID1-3 Input
Segment Data for GRID1 Input
Segment Data for GRID2 Input
Segment Data for GRID3 Input
Digital Dimming Data Input
Key scan Stop
Switch Data Output
A/D Data Output
OPERATING MODE
M0
FUNCTION DATA
0
1
0
1
0
1
0
1
M1
0
0
1
1
0
0
1
1
M2
0
0
0
0
1
1
1
1
FEDL9227-01
ML9227
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