bu9768ak ROHM Co. Ltd., bu9768ak Datasheet
bu9768ak
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bu9768ak Summary of contents
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... BU9768AK / BU9768AKV The BU9768AK / BU9768AKV are man-machine interface ICs with key input, designed for portable multimedia termi- nals and other devices. They can be used as drivers for operation mode display LCD panels on portable terminals, household products, car stereos, and other appliances 126 cells can be displayed, and keys can be input ...
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... DD2 OSC Fig.1 BU9768AK / BU9768AKV ...
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... OSC, DO – 0 COM ~ COM — — pin. SS BU9768AK / BU9768AKV Processing if not used . . DD2 . DD1 Limits Unit – 300 800 mW 750 – 125 C OPEN OPEN ...
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... DD COM ~ COM – 1 – 1 COM ~ COM – 1 — 30 — — — 200 BU9768AK / BU9768AKV Max. Unit V C Max. Unit — — — 0. — 0. — 6 — 6 — ...
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... Constants should be set to match 1 data communications. : 47k (fosc = 38kHz) : 1000pF (fosc = 38kHz) : 0.047 10k Key matrix (30 maximum) Fig. 2 BU9768AK / BU9768AKV Unit kHz (Note 2) LCD panel (EP ) · · · · · · · · · · · · S ...
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... The constant should be set to match the panel, through testing or other means . : 0.047 10k Key matrix (30 maximum) Fig. 4 BU9768AK / BU9768AKV LCD panel (EP ) · · · · · · · · · · · · COM 1 COM ...
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... GND (fosc = 38kHz) 0.047 F Key matrix (30 maximum) Fig. 5 BU9768AK / BU9768AKV LCD panel (EP ) · · · · · · · · · · · · COM 1 COM 2 COM ...
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... Circuit operation (1) Data communications The BU9768AK / BU9768AKV are able to receive LCD display data output from the controller, as well as the results of key scans. 1) LCD display data output (from controller) When LCD data is output, the command code “42” must be output at the beginning of the data. Fig. 6 shows an example of LCD display data output ...
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... 112 115 118 121 124 BU9768AK / BU9768AKV COM COM ...
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... D 2. Control codes The BU9768AK is designed to support various applications, depending on the combination of control codes used. • DP: Display mode control Depending on the type of display, either bias drive bias drive may be selected. ...
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... BU9768AK / BU9768AKV Max. no. Max. of display key segments input 120 30 114 30 111 30 108 30 123 25 117 25 114 25 111 25 126 ...
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... Standard ICs 2) Transmission of key data A command code of “43” should be input in order to output the results of a key scan to the BU9768AK / BU9768AKV LSB there is data in the key buffer, DO will be LOW changed to HIGH level after the command code is input, the data in the key buffer is output synchronized to the rise of CK ...
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... Key scans and key data communications With the BU9768AK / BU9768AKV, if normal key input is received, DO changes from HIGH to LOW con- nected to the interrupt input pin of the controller, interrupt processing can be carried out based on the key input. Also, after DO changes to LOW following completion of a key scan, a new key scan cannot be carried out until all of the key data has been read ...
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... KEY9 KEY12 KEY13 KEY14 KEY17 KEY18 KEY19 KEY22 KEY23 KEY24 KEY27 KEY28 KEY29 and S have been set to 0 and 1, respectively. In this case BU9768AK / BU9768AKV KEY5 KEY10 Enlarged view of one key KEY15 KEY20 KEY25 Key input received KEY30 Kl 5 ...
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... After a key scan has been successfully completed, no new key scans can be carried out until reading of the key data has been completed. Waiting for key input Has key been input? Yes Key input (key scan starts) Was key scan successful? Yes DO LOW Waiting for input of key data read code Fig. 12 Key scan flow BU9768AK / BU9768AKV ...
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... 384) OSC 1 frame BU9768AK / BU9768AKV When (0, 0, 0): 3n-2 3n-1 3n Out for all COMs When (0, 0, 1): 3n-2 3n-1 3n Lights between COM and Sn only 1 When (1, 0, 1): 3n-2 ...
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... 384) OSC BU9768AK / BU9768AKV When (0, 0, 0): 3n-2 3n-1 3n Out for all COMs When (0, 0, 1): 3n-2 3n-1 3n Lights between COM and Sn only 1 When (1, 0, 1): ...
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... Standard ICs (4) RST and display control After the power supply has been turned on, because the internal data of the BU9768AK / BU9768AKV (D unstable, RST goes LOW at the same time that the power supply is turned on. While RST is LOW, data is transmit- ted using the microcomputer, and when data transmission has been completed, RST can be set to HIGH to prevent meaningless displays ...
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... If data is being transferred before a key scan is carried out, after the power supply is turned on, these precautions do not apply. Fig. 15 When CK is stopped at HIGH Fig. 16 When CK is stopped at LOW to KO line, other keys should not be used for functions 3 6 BU9768AK / BU9768AKV CK rises at least twice CK rises at least twice 19 ...
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... When not using the external reset terminal 4.5V DD • External dimensions (Units: mm) BU9768AK 16.4 0.3 14.0 0 0.8 0.35 0.1 QFP-A64 20 has to satisfy the following conditions. DD Instruction receipt possible t 1ms WAIT 0 < t < 10ms ON 0.15 0.1 0.15 BU9768AK / BU9768AKV at 4.5V or more < 0.3V DD BU9768AKV 12.0 0.3 10.0 0 0.125 0.1 0.5 0.2 0.1 0.1 VQFP64 ...