HT1621B Holtek, HT1621B Datasheet
HT1621B
Specifications of HT1621B
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HT1621B Summary of contents
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RAM Mapping 32´4 LCD Controller for I/O mC Features · Operating voltage : 2.4V~5.2V Built-in 256kHz RC oscillator · External 32.768kHz crystal or 256kHz · frequency source input Selection of 1/2 or 1/3 bias, and selection of · 1/2 or ...
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Block Diagram Note: CS: Chip selection BZ, BZ: Tone outputs WR, RD, DATA: Serial interface COM0~COM3, SEG0~SEG31: LCD outputs IRQ: Time base or WDT overflow output 2 April 21, 2000 HT1621 ...
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Pin Assignment - - - 3 HT1621 April 21, 2000 ...
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Pad Assignment Chip size: 127 ´ 129 (mil) * The IC substrate should be connected to VDD in the PCB layout artwork April 21, 2000 HT1621 ...
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Pad Coordinates Pad No -55.04 2 -58.52 3 -58.52 4 -58.52 5 -58.52 6 -58.52 -11.14 7 -58.52 -34.76 8 -58.52 -41.90 9 -58.52 -49.13 10 -58.52 -59.08 11 -44.07 -59.08 12 -31.58 -59.08 13 -20.70 -59.08 14 ...
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Pad Description Pad No. Pad Name I/O Chip selection input with pull-high resistor When the CS is logic high, the data and command read from or written to the HT1621 are disabled. The serial interface circuit ...
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D.C. Characteristics Symbol Parameter V V Operating Voltage DD I Operating Current DD1 I Operating Current DD2 I Operating Current DD3 I Standby Current STB V Input Low Voltage IL V Input High Voltage IH I DATA, BZ, BZ, IRQ ...
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A.C. Characteristics Symbol Parameter f System Clock SYS1 f System Clock SYS2 f System Clock SYS3 f LCD Clock LCD t LCD Common Period COM f Serial Data Clock (WR pin) CLK1 f Serial Data Clock (RD pin) CLK2 f ...
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Figure 1 Figure 3 Functional Description Display memory - RAM The static display memory (RAM) is organized into 32´4 bits and stores the displayed data. The contents of the RAM are directly mapped to the contents of the LCD driver. ...
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At the initial system power on, the HT1621 is at the SYS DIS state. Time base and Watchdog Timer (WDT) The time base generator ...
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Name Command Code LCD OFF LCD BIAS & COM ...
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OFF command turns the LCD display off by dis- abling the LCD bias generator. The LCD ON command, on the other hand, turns the LCD display on by enabling the LCD bias generator. The BIAS and COM are the LCD ...
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Timing Diagrams READ mode (command code : READ mode (successive address reading) 13 April 21, 2000 HT1621 ...
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WRITE mode (command code : WRITE mode (successive address writing) 14 April 21, 2000 HT1621 ...
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READ-MODIFY-WRITE mode (command code : READ-MODIFY-WRITE mode (successive address accessing) 15 April 21, 2000 HT1621 ...
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Command mode (command code : Mode (data and command mode) Note recommended that the host controller should read in the data from the DATA line between the rising edge of the RD line and the ...
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Application Circuits Host controller with an HT1621 display system m Note: The connection of IRQ and RD pin can be selected depending on the requirement of the mC. The voltage applied to V pin must be lower than V LCD ...
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Command Summary Name ID Command Code READ A5A4A3A2A1A0D0D1D2D3 WRITE A5A4A3A2A1A0D0D1D2D3 READ- MODIFY A5A4A3A2A1A0D0D1D2D3 WRITE SYS DIS 0000-0000-X SYS 0000-0001-X LCD OFF ...
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Name ID Command Code IRQ 100X-1XXX 101X-X000 101X-X001 101X-X010 101X-X011-X F16 101X-X100-X F32 101X-X101-X ...
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... Holtek reserves the right to alter its products without prior notification. For the most up-to-date information, please visit our web site at http://www.holtek.com.tw. ...