UPD16431A NEC, UPD16431A Datasheet
UPD16431A
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UPD16431A Summary of contents
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LCD CONTROLLER/DRIVER The PD16431A is an LCD controller/driver that enables display of segment type LCDs of 1/2, 1/3, or 1/4 duty cycle. This controller/driver has 56 segment output lines of which eight can also be used as ...
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BLOCK DIAGRAM Key counter Write address STB DATA I/O 56-bit shift register control CLK 8-bit Command shift decoder register 8 KEY REQ LED Segment driver driver 56 Level shifter (56) 56 Selector circuit 56 Timing ...
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... SEG /LED 52 4 SEG /LED 53 5 SEG /LED 54 6 SEG /LED SEG /LED Note Though V and V are internally connected, be sure to connect all the power supply pins ( and V ). LCD EE PD16431A 41 40 SEG 16 SEG 15 SEG 14 SEG 13 SEG 12 SEG 11 SEG ...
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... LC1 LC3 drive Note the key data cannot be written correctly, even when the display ON/OFF of the status command is set to the “normal operation” (10). Also, in this state, unnecessary waveforms are generated from between SEG 4 No. Description These pins serve as LCD segment output pins and key source output pins for key scanning ...
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CONFIGURATION OF SHIFT REGISTER Two shift registers, an 8-bit command register and a 56-bit display register, are provided. The first 8 bits of input data are recognized as a command and are sent to the command register, and the 9th ...
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KEY MATRIX CONFIGURATION An example of key matrix configurations is shown below. 1) When pressing three or more times is assumed: A configuration example is shown below. recognized. KEY 1 KEY 2 KEY 3 KEY ...
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If diode A is not available, not only the key data may not be read normally but the LCD display may be affected or ICs may be damaged or deteriorated. For example, if SW1 and SW2 are ON and KS ...
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CONFIGURATION OF KEY DATA LATCH The key data is latched as illustrated below and is read by a read command, starting from the most significant bit. Key data is read once a frame and latched when coinciding with the immediadtely ...
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COMMAND A command sets a display mode and a status. The first 1 byte input after the STB pin has fallen is regarded as a command. If the STB pin is made low while a command/data is transferred, serial communication ...
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Status command This command sets a data write/read mode, turns on/off display, and sets a latch address. MSB Values when power is applied LSB b0 : Don’t Care Sets ...
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OUTPUT SELECT VOLTAGE 1. COM + When selected V LCD V LCD When not selected 1/2 V LCD V LC2 When key scanned 1/2 V LCD V LC2 When selected V LCD V LCD When not selected 1/3 V LCD ...
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OUTPUT WAVEFORM (1) 1/2 duty (1/2 dias LCD COM V 1 LC2 LCD COM V 2 LC2 LCD SEG V 1 LC2 LCD SEG V 9 ...
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KEY SCAN PERIOD (K0) EXPANSION LCD COM V 1 LC2 LCD SEG V 1 LC2 LCD SEG V 2 LC2 LCD SEG V 3 LC2 V EE ...
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KEY SCAN PERIOD (K1) EXPANSION LCD COM V 1 LC2 LCD SEG -SEG LC2 SEG -SEG LCD SEG V 5 LC2 LCD ...
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LCD V LC1 COM V 1 LC2 V LC3 LCD V LC1 COM V 2 LC2 V LC3 LCD V LC1 COM V 3 ...
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KEY SCAN PERIOD (K0) EXPANSION LCD V LC1 COM V 1 LC2 V LC3 LCD V LC1 SEG V 1 LC2 V LC3 LCD V LC1 SEG V 2 LC2 V ...
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KEY SCAN PERIOD (K1) EXPANSION LCD V LC1 COM V 1 LC2 V LC3 LCD V LC1 SEG -SEG LC2 SEG -SEG LC3 LCD V ...
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KEY SCAN PERIOD (K2) EXPANSION LCD V LC1 COM V 1 LC2 V LC3 LCD V LC1 SEG -SEG LC2 V LC3 ...
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LCD V LC1 COM V 1 LC2 V LC3 LCD V LC1 COM V 2 LC2 V LC3 LCD V LC1 COM V LC2 ...
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KEY SCAN PERIOD (K0) EXPANSION LCD V LC1 COM V 1 LC2 V LC3 LCD V LC1 SEG V 1 LC2 V LC3 LCD V LC1 SEG V 2 LC2 V ...
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KEY SCAN PERIOD (K1) EXPANSION LCD V LC1 COM V 1 LC2 V LC3 LCD V LC1 SEG -SEG LC2 SEG -SEG LC3 LCD V ...
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KEY SCAN PERIOD (K2) EXPANSION 1 V LCD V LC1 COM V 1 LC2 V LC3 LCD V LC1 SEG -SEG LC2 V LC3 V EE KEY SCAN PERIOD (K3) EXPANSION 2 V LCD ...
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... STB DATA b7 SCK 1 2 (2) Transmit (command/data read) STB DATA 7 6 SCK Data read command set Note Because the DATA pin is an N-ch open-drain output pin, be sure to connect an external pull-up resistor to this pin ( ...
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APPLICATION 1. Example of initial setting + display data write Command/data Parameter STB Start H Set display command Status command L 1 ...
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Example of display data write (rewrite, 1/4) Command/data Parameter STB Start H Status command Display data 1 L Display data 7 L ...
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Example of key data read Command/data Parameter STB KEY REQ check Start H Status command Wait time L Key data 1 L ...
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ABSOLUTE MAXIMUM RATINGS (T Parameter Symbol Logic supply voltage V DD Logic input voltage V IN Logic output voltage (DATA) V OUT LCD drive supply voltage V LCD LCD drive supply input voltage LC1 Driver output voltage ...
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ELECTRICAL SPECIFICATIONS (Unless otherwise specified, T Parameter Symbol Input voltage, high V IH Input voltage, low V IL Input current, high I IH Input current, low I IL Output voltage, low V OL1 Output voltage, high V OH2 Output voltage, ...
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SWITCHING CHARACTERISTICS (Unless otherwise specified –40 to +85 ˚ Parameter Symbol Oscillation frequency f OSC Oscillation frequency f OSC Propagation delay time t PZL Propagation delay time t PLZ SYNC delay time t DSYNC TIMING REQUIREMENTS ...
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Switching Characteristic Waveform CSC IN STB WLK V IH SCK DATA V IL SYNC timing (master) 1 frame f OSC SYNC Internal reset 30 1 WHC ...
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... V GND (V PD16431A LCD Key matrix LCD R 8 LED 1 100 k TYP 330 through R are not necessary when 1 2 through V are open). LC1 LC3 31 ...
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Note Example of external source circuit (when 1/2 bias GND The application circuits and their parameters are for references only and are not intended for use in actual design-in' ...
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PIN PLASTIC LQFP ( 14 NOTE Each lead centerline is located within 0.13 mm (0.005 inch) of its true position (T.P.) at maximum material condition ...
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... Specific: Aircrafts, aerospace equipment, submersible repeaters, nuclear reactor control systems, life support systems or medical equipment for life support, etc. The quality grade of NEC devices in “Standard“ unless otherwise specified in NEC's Data Sheets or Data Books. If customers intend to use NEC devices for applications other than those specified for Standard quality grade, they should contact NEC Sales Representative in advance ...