309-509 Datasheet | RS Components

data lssued November1984 4080 Keyboardencoder i.c.309-509 T|e RS2376 Keyboard Encoder l.C. is a fully integrated P-MOS keyswitch encoding circuit, suitable for encoding a keyboard with up to 88 switches, plus shift and control, into a useable9 bit data code, i.e.the standard8 bit ASC ll datacode + one parity bit. The RS2376offers the facilities of two key roll-over operation with N-key lockout and has userselectableodd or even parity and output polarity.A self contained oscillator and debouncecircuit are incorporated in the device, requiring only the addition of a resistor and capacitor for each function. The outputs are directly TTL/MOS logic patible. The RS 76 key Keyboard (336-703)is designedto accept the RS2376Keyboard Encoder LC.,enabling a full ASCIIcode keyboardto be easilyconstructed. Features o One integrated circuit required for plete keyboard assembly. o Outputs directlypatiblewith TTLor MOSlogic arrays. o External control provided for output polarity selection. . External control provided for selectionof odd or even parity. o Two key roll-overoperation. o N-keylockout. o Self-containedoscillatorcircuit. o Externally controlled delay network provided to eliminate the effectof contactbounce. o Static charge protection on all input and output terminals. Figure'l Pinconnections Figure2 Block diagram lll '- l qmrnr rg I ^'l- l ,MSn- 19A[r A(ES r 3MGt r.l . Rl lc8old Ct (.maa Fl m OVIDE FPSgt't.5mr r' R2ltootl,C2l3op Fl O€LAY Pn OVDE s Or H: Cl-OCl( FREOUEi TY nru T(o?Ttot{l Electrica I characteristics Maximum ratings V61and V66(with respectto Vcc) -20Vto +0.3V logic input voltages (with respectto Vcc) -20 V to 0.3V Storage Temperature -65"Cto +150"C Operating Temperature Rarrge 0"Cto +70'C Exceedingthese ratings could causepermanentdamage. F u n c t i o n a lo p e r a t i o n o f t h i s d e v i c e a t t h e s e c o n d i t i o n s i s n o t implied-operating rangesare specifiedbelow. Standard Gonditions (unlessotherwise...