K25C81-FB Semtech, K25C81-FB Datasheet
K25C81-FB
Related parts for K25C81-FB
K25C81-FB Summary of contents
Page 1
... PC/XT/AT/PS2 system, and/or any optional keyboard-compatible devices, such 101/102 standard desktop keyboard, OCR, barcode reader, etc. The K25C81 directly interfaces a PC keyboard port, making custom keyboard to system communications fully transparent matrix, the ...
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... Copyright Semtech, 1997-2001 DOC5-C81-DS-105 ORDERING CODE Package options Pitch In mm’s 40-pin, Plastic DIP 2.54 mm 44-pin, Plastic PLCC 1.27 mm 44-pin, Plastic QFP 0.8 mm Keyboard Encoder Row Data Inputs Column Select Ouputs Mode Control -40°C to +85°C K25C81-XX-P K25C81-XX-FN K25C81-XX-FB R0-R7 8 C0-C17 18 RP www.semtech.com ...
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... Each key press is debounced for a period of 20 mS. Once the key is verified, the corresponding key code(s) are loaded into the transmit buffer of the PC Keyboard Communication Channel. Copyright Semtech, 1997-2001 DOC5-C81-DS-105 PIN DEFINITIONS Mnemonic DIP PLCC QFP Vcc ...
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... Should the external keyboard be removed at a later time, the K25C81 detects the disconnection and will reinitiate the reset sequence upon reconnection. This feature allows the user to connect and disconnect an external keyboard at any time without resetting the system ...
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... AT/PS/2 protocol and can be sent to the keyboard at any time. Mode 1 accepts only the ‘reset’ command. Commands shown in italics do not affect the operation of the K25C81. Nevertheless, they are acknowledged and relayed to the external keyboard external standard keyboard is present. The following table shows the commands that the keyboard may send to the system ...
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... C14 C13 C12 C11 C10 VCC (c)1994-2001 USAR SYSTEMS, Inc. Application Circuit for K25C81-FB .6 Rev K25C81FB.sch Document Number F35 F33 F37 F30 F31 F32 F22 F21 F25 ; [ F20 t u F23 m n F18 ...
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... SUGGESTED INTERFACING FOR K25C81-FB (44-PIN QFP PACKAGE) 2 Copyright Semtech, 1997-2001 DOC5-C81-DS-105 ODCO VCC 38 OSCI RST VSS www.semtech.com ...
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... MECHANICALS FOR THE K25C81 Copyright Semtech, 1997-2001 DOC5-C81-DS-105 Seating Plane Notes: 1. Positional tolerance of leads (D) shall be within 0.25 mm (0.010) at maximum material condition, in relation to the seating plane and each other. 2. Diminsion the center of the leads when the leads are formed parallel ...
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... MECHANICALS FOR THE K25C81-FN L (Note (Note 0.25 (0.010 Copyright Semtech, 1997-2001 DOC5-C81-DS-105 Y BRK Leads PLCC 0.18 (0.007 0.18 (0.007 Detail S ...
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... MECHANICALS FOR THE K25C81- Detail 0.20 (0.008) C A-B M 0.05 (0.002) A-B S 0.20 (0.008) H A-B M Datum Plane H W Detail Seating G Plane H Copyright Semtech, 1997-2001 DOC5-C81-DS-105 0.20 (0.008 Section B ...
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... Ratings Symbol Supply Voltage Vdd Input Voltage Vin Current Drain per Pin I (not including Vss or Vdd) Operating Temperature Ta K25C81 Storage Temperature Range Tstg Thermal Characteristics Characteristic Symbol Thermal Resistence Tja Plastic DIP Plcc DC Electrical Characteristics (Vdd=5.0 Vdc +/-10%, Vss=0 Vdc, Temperature range=T low to T high unless otherwise noted) ...
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... Telefax Copyright 1997-2001 Semtech Corporation. All rights reserved. KeyCoder, FlexiCoder and Self-Power Management are trademarks of Semtech Corporation. Semtech is a registered trademark of Semtech Company. All other trademarks belong to their respective companies. INTELLECTUAL PROPERTY DISCLAIMER This specification is provided "as is" with no warranties whatsoever ...