K25C81-P

K25C81-FB SEMTECH | Alldatasheet

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Versatile PC/XC/AT/PS/2 Compatible Keyboard Encoder FlexiCoderTM is a trademark of Semtech Corp. All other trademarks belong to their respective companies. Copyright Semtech, 1997-2001 DOC5-C81-DS-105 www.semtech.com1 HID & SYSTEM MANAGEMENT PRODUCTS, KEYCODERTM FAMILY DESCRIPTION FEATURES 1_RESET 40 Vcc OSCI OSCO EKC1 NC C10 C11 C12 C13 C14 C15 _IRQ VX C17 RP KD KC EKC EKD C16 Vss 2 39 3 38 4 37 5 36 6 35 7 34 8 33 9 32 10 31 11 30 12 29 13 28 14 27 15 26 16 25 17 24 18 23 19 22 20 21 DIP C17 VX NC _IRQ _RESET VCC OSCI OSC0 EKC1 NC RP KD KC EKC EKD C16 NC C10 NC VSS NC C15 C14 C13 C12 C11 18 23 28 39 R6 RP KD KC EKC EKD C16 C17 VX _IRQ _RESET NC NC VCC OSCI OSCO EKC1 NC C10 C11 NC VSS C15 C14 C13 C12 NC PLCC QFP

• Custom keyboards/keypads  Control panels  Automatic teller machines  Embedded control systems  Public Information Kiosks  Instrumentation  Test and Measurement equipment  Point of Sales terminals  Industrial Controllers  Medical Instruments  Enables custom keypad scan codes to remain unaffected by the Shift States of an external keyboard  Includes jumper-selectable auto- repeat for designated keys  Offers two-key inhibit scanning mode  Directly interfaces a PC keyboard port  Encodes up to 144 custom keys on an 8 X 18 matrix  Buffers up to 122 keycodes  Interfaces to 83/101/102 standard keyboard or other 8042-compatible device The FlexiCoderTM is a versatile, low- power keyboard encoder. It offers two bi-directional channels for communicating with a PC/XT/AT/PS2 system, and/or any optional keyboard-compatible devices, such as an 83 or 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. On an 8 x 18 matrix, the FlexiCoder TM will scan, debounce and encode up to 144 keys. Scan codes corresponding to single keys of the IBM 101 keyboard, or a combination of these keys when depressed with Shift, Ctrl, and Alt keys, are generated with each key press. Custom keypad input is not effected by the Shift States of an external keyboard. Users can conveniently define key assignments on the matrix as single or repeating actions. All keys must be released between key strokes or scanning is suspended. The encoder can buffer up to 122 keycodes, and control inputs and outputs are provided for interfacing with contact keyboards. The FlexiCoder TM is ideal for use with either BIOS-compatible chip sets or single-board computers for PC systems requiring a custom keyboard / keypad as an alternate or additional input device. Boards and evaluation kits are immediately obtainable and ready to connect.

APPLICATIONS

Copyright Semtech, 1997-2001 DOC5-C81-DS-105 www.semtech.com2 Package options 40-pin, Plastic DIP 44-pin, Plastic PLCC 44-pin, Plastic QFP Pitch In mm’s 2.54 mm 1.27 mm 0.8 mm TA = -40°C to +85°C K25C81-XX-P K25C81-XX-FN K25C81-XX-FB Data Buffer Interrupt Control PC Communication Channel

8042 Emulation

(Standard Keyboard) Communication Channel EKC1 KC KD EKC EKD Keyboard Encoder Mode Control Row Data Inputs Column Select Ouputs R0-R7 RP C0-C17

FUNCTIONAL DESCRIPTION PIN DEFINITIONS Copyright Semtech, 1997-2001 DOC5-C81-DS-105 www.semtech.com3 Mnemonic DIP PLCC QFP TYPE Name and Function Vcc 40 44 38 I Power Supply: +5V Vss 20 22 17 I Ground OSCI 39 43 37 I Oscilator Input OSCO 38 42 36 O Oscilator Output _RESET 1 1 41 I Reset: apply 0 V to provide orderly start-up. _IRQ 2 2 42 I Must be tied to Vcc VX 3 4 43 I Tie to Vcc. R P 672I Rollover Mode Selection: tie to Vcc to select N-Key Rollover. Tie to Ground to select Two-Key Inhibit Mode. K C 894I / O Keyboard Clock: connects to PC’s keyboard port Clock Line. K D 783I / O Keyboard Data: connects to PC’s keyboard port Data Line. EKD 10 11 6 I/O External Keyboard Data: connects to external keyboard Data Line. EKC 9 10 5 I/O External Keyboard Clock: connects to external keyboard Clock Line. EKC1 37 41 35 I External Keyboard Clock 2: connects to external keyboard Clock Line and is used to generate an interrupt for every Clock Line transition. This signal must be inverted for PC/XT keyboards. C0-C7 12-19 3-17 8-15 O Column Select Outputs: select 18 one of columns. 19-21 C8-C15 28-21 31-24 26-18 C16 11 12 7 O C17 4 5 44 I/O Keyboard type selection: this pin is used both as outputs for column select and as input for standard keyboard-type selection. R0-R5 29-34 32-37 27-32 I Row data inputs R 6 561I R7 36 39 34 I NC 35 38, 3 16, 33 - No Connects: these pins are 18, 23 22, 39 - unused. 40 40 Note: An underscore before a pin mnemonic denotes an active low signal. The FlexiCoderTM consists of six major sections (see functional diagram, previous page). These are the Keyboard Encoder, the Mode Control Unit, the PC Communication Channel, the 8042 Emulation Channel, the Interrupt Control Unit and the Data Buffer. These sections communicate with each other and operate concurrently. The controller continuously scans a keyboard organized as an 8 row by 18 column matrix, for a maximum of 144 keys. Smaller-size keyboards can be connected provided that all unused row pins are connected to Vcc. The microcontroller selects one of the 18 column lines (C0-C17) every 512 µS and then reads the row data lines (R0-R7). A key closure is detected as a zero in the corresponding position of the matrix. A complete scan cycle for the entire keyboard takes approxi- mately 9.2 mS. 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.

REPEAT KEYS FUNCTIONAL DESCRIPTION, (CON’T) Copyright Semtech, 1997-2001 DOC5-C81-DS-105 www.semtech.com4 In custom masks, each key can be defined individually to be either Typematic or Single-Touch Action. In the standard mask, all keys are defined to be Single-Touch Action, except the Arrow Keys. Pin RP controls the repeat action of keys that are defined to be Typematic. Table 1: Typematic Action Control The Typematic rate can be controlled by issuing the appropriate commands from the system. Repeat Mode RP No repeat action L Repeat action H Switch Matrix Encoding Each matrix location is programmed to represent either a single key or a combination of keys of the IBM-standard 101/102 keyboard. Scan Code Table Sets The FlexiCoderTM supports two scan code table sets. Scan Code Sets 1 and 2 are the default sets for PC/XT and AT/PS/2 systems respectively. For more information, refer to the IBM Technical Reference Manual. Custom scan code tables, including macros, are also available. Operating modes are defined by the logic level of the relevant mode pins in the Mode Control Unit. Scan Matrix Data Integrity The FlexiCoderTM maintains the integrity of the codes corresponding to the scanned matrix locations, independently of the Shift Status of the external keyboard or the system. For example, if a key has been defined on the matrix to send code corresponding to lower case letter “a”, it will still send the scan code for “a” even if the Shift Key has been pressed or the Caps Lock has been set by the external keyboard. This is accomplished by internally maintaining a set of flags to monitor the Shift Status of the external keyboard and the system. If, for instance, the lower case key “a” is found to be pressed and Caps Lock is set, the codes sent will be as follows: 1. Caps Lock Make Code 2. Caps Lock Break (this will reset the Caps Lock status of the system) 3. “a” Make Code 4. “a” Break Code 5. Lock Make Code 6. Caps Lock Break Code (this will restore the Caps Lock status of the system) SPECIAL HANDLING SPECIAL HANDLING, (CON’T) External Keyboard Connection If an external keyboard was not connected during power-on and then connected at a later time, the controller will proceed with the normal reset routine in order to initialize the external keyboard properly. Thereafter, the FlexiCoder TM checks for the presence of an external keyboard every 2 seconds. After communication has been established, the controller continues checking for the external keyboard’s presence. 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.

EXT. KBD COMMUNICATION MODE CONTROL Copyright Semtech, 1997-2001 DOC5-C81-DS-105 www.semtech.com5 The external keyboard communication port of the FlexiCoder TM fully emulates a standard 8042, available to an 83/101/102 external keyboard or other compatible device. Communication with an external keyboard is accomplished via EKC and EKD, Clock and Data lines respectively. A third pin, EKC1 which connects to the Clock Line, interrupts the controller whenever an external keyboard initiates a communication. When power is first applied, the controller proceeds with the standard reset sequence with the external keyboard. Data and commands coming from the external keyboard are buffered in the controller’s FIFO, along with data from the scanned matrix, and then presented to the system as if originating from a single source. Commands and data from the system, after being acknowledged, are then transmitted to the external keyboard. The FlexiCoderTM implements all the standard functions of communication with a BIOS- compatible PC/XT or AT/PS/2 host system. Two lines, KC and KD, provide bi-directional clock and data signals according to the protocol (PC or AT) selected. In addition, the K25C81 supports commands from and to the system, as described in the IBM Technical Reference Manuals. The following table shows the commands that the system may send and their value in hex. Command Hex Value Set/Reset Status ED Indicators Echo EE Invalid Command EF Select Alternate F0 Scan Codes Invalid Command F1 Read ID F2 Set Typematic F3 Rate/Delay Enable F4 Default Disable F5 Set Default F6 Set All Keys Typematic F7 Make/Break F8 Make F9 Typematic/Make/Break FA Set Key Type Typematic FB Make/Break FC Make FD Resend FE Reset FF Table 2: Keyboard Commands from the System (AT/PS/2 protocol) These commands are supported in the 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, if an external standard keyboard is present. The following table shows the commands that the keyboard may send to the system. Command Hex Value Key Detection 00* Error/Overrun Keyboard ID 83AB BAT Completion Code AA BAT Failure Code FC Echo EE Acknowledge (Ack) FA Resend FE Key Detection Error/Overrun FF* *Scan Code Set 2 Table 3: Keyboard Commands to the System (AT/PS/2 protocol) When an external keyboard is connected, commands from the system will also be directed to the external keyboard. Presence or absence of an external keyboard will not affect the normal operation of the FlexiCoder TM.

SUGGESTED INTERFACING FOR K25C81-FN (44-PIN PLCC PACKAGE) Copyright Semtech, 1997-2001 DOC5-C81-DS-105 www.semtech.com6 4x47pF 2x2K2x4.7K TELCOM AVX PBRC4.00BR JUPERS SETTINGS JP1 1-2: PC/XT PC/AT2-3 K25C81FB.sch .6 Application Circuit for K25C81-FB (c)1994-2001 USAR SYSTEMS, Inc. Document Number Rev C15 C14 C13 C12 C11 C10 C16 C17 R7R5 VC C VCC VC C VC C VC C VC C RP1 NET_15K TC54VC4502EC B K25C81-FN PLCC RST VCC C17 C16 NC EKD KC KD VX OSCI ODCO VSS C15 C14 C13 C12 C11 C10 NC EKC1 EKC IRQ RP NC C4A R7A .1uF R4R3R2 R6 100KR1 C5C4C3 JP1 4.00MHz + C6 10uF EXTERNAL_KBD_PS2DAT A EXTERNAL_KBD_PS2CLOC K HOST_PS2DAT A HOST_PS2CLOC K Rows (R0-R7) 01234567 F29 F28 End F36 F34 F35 F33 F37 Pg Dn Home PgUp : F27 F30 F31 F32 ]()*^ F 2 2 F 2 1 F 2 5 vw xyz; [ F 2 0 opqr st uF 2 3 h ijk lm n F 1 8 abcdef gi . , (comma) - (dash) / % & # 0 STUVW XYZ JK LM N O PQ ABCDEF GH 12345678 f3 f4 f6 f5 f7 f8 f9 f2 f14 f13 f12 f15 f11 f16 9 f10 f1 Backspace Rt Arrow* Dn Arrow* F38 Space F19 + Ins Esc Up Arrow* Lft Arrow* R Enter $ = ’(Apostrophe) " < > ? ~ Tab Del * Typematic Keys n Upper case A–Z correspond to Shift a–Shift z n F11–F20 correspond to Shift F1–Shift F10 n F21–F30 correspond to Ctrl F1–Ctrl F10 n F31–... correspond to Alt F1–Alt F10 Columns (C0–C17) STANDARD KEYMAP FOR K25C81

SUGGESTED INTERFACING FOR K25C81-FB (44-PIN QFP PACKAGE) Copyright Semtech, 1997-2001 DOC5-C81-DS-105 www.semtech.com7 4x47pF 2x2K2x4.7K TELCOM AVX PBRC4.00BR JUPERS SETTINGS JP1 1-2: PC/ XT PC/AT2-3 K25C81FB.sch .6 Application Circuit for K25C81-FB (c)1994-2001 USAR SYSTEMS, Inc. Document Number Rev C15 C14 C13 C12 C11 C10 C16 C17 VC C VCC VC C VC C VC C VC C RP1 NET_15K TC54VC4502EC B 2 3 .1uF K25C81-FB QFP44 24. RST VCC C17 C16 NC EKD KC KD NC VX OSCI ODCO VSS C15 C14 C13 C12 C11 C10 NC NC EKC1 EKC IRQ RP NC R4R3R2 R6 100KR1 C5C4C3 JP1 4.00MHz + C6 10uF EXTERNAL_KBD_PS2DAT A EXTERNAL_KBD_PS2CLOC K HOST_PS2DAT A HOST_PS2CLOC K

MECHANICALS FOR THE K25C81-P Copyright Semtech, 1997-2001 DOC5-C81-DS-105 www.semtech.com8 40 21 1 20 B A Seating Plane N KDFGH C L J M 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 L is to the center of the leads when the leads are formed parallel. 3. Dimension B does not include mold flash. B C D F G H J K L M N 13.72 14.22 0.540 0.560 3.94 5.08 0.155 0.200 0.36 0.56 0.014 0.022 1.02 1.52 0.040 0.060 2.54 BSC 0.100 BSC 2.16 0.085 0.20 0.008 2.92 0.015 15 0 15 0.51 1.02 0.020 0.040 MIN MAX MIN MAX MILLIMETERS INCHES DIM 0 0 0 A 51.69 52.45 2.035 2.065 0.38 0.015 0.1353.43 15.24 BSC 0.600 BSC 1.65 0.065

MECHANICALS FOR THE K25C81-FN Copyright Semtech, 1997-2001 DOC5-C81-DS-105 www.semtech.com9 W Y BRK D D V N ML 1(Note 1) 44 Leads PLCC P Z G C A R E J44 (Note 1) Detail S G1X Note 1 U B A B C E F G H J K R U V W X Y Z 17.40 17.65 0.685 0.695 17.40 17.65 0.685 0.695 4.20 4.57 0.165 0.180 2.29 2.79 0.090 0.110 0.33 0.48 0.013 0.019 1.27 BSC 0.050 BSC 0.66 0.81 0.026 0.032 0.51 - 0.020 - 0.64 - 0.025 - 16.51 16.66 0.650 0.656 16.51 16.66 0.650 0.656 1.07 1.21 0.042 0.048 - 0.50 - 0.020 2 10 2 10 15.50 16.00 0.610 0.630 1.02 - 0.040 - 2 10 2 10 MIN MAX MIN MAX MILLIMETERS INCHES 1.07 1.21 0.042 0.048 1.07 1.42 0.042 0.056 DIM 0 0 K F H 0.18 (0.007) 0.18 (0.007) T T -L S M S N S P S L S M SN S P S 0.18 (0.007) 0.18 (0.007) T T -L S M S N S P S L S M SN S P S 0.18 (0.007) T L S M SN S P S 0.18 (0.007) T L S M SN S P S 0.18 (0.007) T -L S M S N S P S 0.25 (0.010) T -L S M S N S P S Seating PlaneT 0.010 (0.004) 0.18 (0.007) T -L S M S N S P S Notes: 1. Due to space limitation, the chip is represented by a general (smaller) case outline drawing rather than showing all 44 leads. 2. Datums L, M, N, and P determine where the top of the lead shoulder exits plastic body at mold parting line 3. DIM G1, true position to be measured at Datum T, Seating Plane 4. DIM R and U do not include mold protusion. Allowable mold protusion is 0.25 (0.010) per side. 5. Dimensioning and tolerancing per Ansi Y14.5M, 1982 6. Controlling dimension: Inch Detail S M M M M 0.25 (0.010) T L S M SN S P S M M - M M View D-D M M

MECHANICALS FOR THE K25C81-FB Copyright Semtech, 1997-2001 DOC5-C81-DS-105 www.semtech.com10 Detail A M Q W K X T R C Datum Plane Detail C L BA L B V D A S C E G M M H Seating Plane H Datum Plane A,B,D 0.20 (0.008) C A-B S D SM 0.05 (0.002) A-B 0.20 (0.008) H A-B S D SM 0.20 (0.008) H A-B S D SM 0.20 (0.008) C A-B S D SM 0.05 (0.002) A-B 0.01 (0.004) B C D E F G H J K L M N Q R S T U V X 9.90 10.10 0.390 0.398 2.10 2.45 0.083 0.096 0.30 0.45 0.012 0.018 2.00 2.10 0.079 0.083 0.30 0.40 0.012 0.016 0.80 BSC 0.031 BSC 0.25 0.010 0.13 0.005 0.65 0.026 5 10 5 10 0.13 0.17 0.005 0.007 13.45 0.530 0.13 0.005 0 0 0.510 0.40 0.016 MIN MAX MIN MAX MILLIMETERS INCHES 0 7 0 7 0.13 .30 0.005 0.012 DIM 0 0 0 0 0 0 JN F Base Metal D 0.20 (0.008) C A-B S D SM Section B-B A 9.90 10.10 0.390 0.398 0.23 0.009 0.0370.95 8.00 REF 0.315 REF 12.95 0.510 W 12.95

1.6 REF

13.45 0.530

0.063 REF

1. Dimensioning and tolerancing per Ansi Y14.5-M, 1982 2. Controlling dimension: Millimeter 3. Datum Plane "H" is located at the bottom of the lead and is coincident with the lead where the lead exits the plastic body at the bottom of the parting line. 4. Datums -A-, -B-, and -D- to be determined at Datum Plane -H-. 5. Dimensions S and V to be determined at seating plane -C-. 6. Dimensions A and B do not include Mold protusion. Allowable protusion is 0.25 (0.010) per side. Dimensions A and B do include mold mismatch and are determined at Datum Plane -H-. 7. Dimension D does not include Danbar protrusion. Allowable Danbar protrusion is 0.08 (0.003) total in excess of the D dimension at Maximum Material Condition. Danbar cannot be located on the lower radius or the foot. B Detail A Detail C 33 23 H

Copyright Semtech, 1997-2001 DOC5-C81-DS-105 www.semtech.com11 Absolute Maximum Ratings Ratings Symbol Value Unit Supply Voltage Vdd -0.3 to +7.0 V Input Voltage Vin Vss -0.3 to Vdd +0.3 V Current Drain per Pin I 25 mA (not including Vss or Vdd) Operating Temperature Ta T low to T high ° C K25C81 40 to +85 Storage Temperature Range Tstg -65 to +150 ° C Thermal Characteristics Characteristic Symbol Value Unit Thermal Resistence Tja ° C per W Plastic 60 DIP -60 Plcc 70 Characteristic Symbol Min Typ Max Unit Output Voltage (I load<10µA) Vol 0.1 V Voh Vdd –0.1 Output High Voltage (I load=0.8mA) Voh Vdd –0.8 V Output Low Voltage (I load=1.6mA) Vol: 0.4 V Input High Voltage Vih 0.7xVdd Vdd V Input Low Voltage Vil Vss 0.2xVdd V Supply Current Idd 4.7 7.0 mA I/O Ports Hi-Z Leakage Current Iil +/-10 µA Input Current Iin +/- 1 µA I/O Port Capacitance Cio 8 12 pF Control Timing (Vdd=5.0 Vdc +/-10%, Vss=0 Vdc, Temperature range=T low to T high unless otherwise noted) Characteristic Symbol Min Max Unit Frequency of Operation fosc MHz Crystal Option 4.0 External Clock Option dc 4.0

Copyright Semtech, 1997-2001 DOC5-C81-DS-105 www.semtech.com12 For sales information and product literature, contact: HID & System Mgmt Division Semtech Corporation

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New York, NY 10012 hidinfo@semtech.com http://www.semtech.com 212 226 2042 Telephone 212 226 3215 Telefax Semtech Western Regional Sales 805-498-2111 Telephone 805-498-3804 Telefax Semtech Central Regional Sales 972-437-0380 Telephone 972-437-0381 Telefax Semtech Eastern Regional Sales 203-964-1766 Telephone 203-964-1755 Telefax Semtech Asia-Pacific Sales Office +886-2-2748-3380 Telephone +886-2-2748-3390 Telefax Semtech Japan Sales Office +81-45-948-5925 Telephone +81-45-948-5930 Telefax Semtech Korea Sales Sales +82-2-527-4377 Telephone +82-2-527-4376 Telefax Northern European Sales Office +44 (0)2380-769008 Telephone +44 (0)2380-768612 Telefax Southern European Sales Office +33 (0)1 69-28-22-00 Telephone +33 (0)1 69-28-12-98 Telefax Central European Sales Office +49 (0)8161 140 123 Telephone +49 (0)8161 140 124 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 including any warranty of merchantability, fitness for any particular purpose, or any warranty otherwise arising out of any proposal, specification or sample. A license is hereby granted to reproduce and distribute this specification for internal use only. No other license, expressed or implied to any other intellectual property rights is granted or intended hereby. Authors of this specification disclaim any liability, including liability for infringement of proprietary rights, relating to the implementation of information in this specification. Authors of this specification also do not warrant or represent that such implementation(s) will not infringe such rights.