ST7920 - Topwaydisplay.com

ST7920AC Characteristics (T A = 25 o C, V DD = 4.5V) Parallel Mode InterfaceSymbol Characteristics Test Condition Min. Typ. Max. UnitInternal Clock Operationf OSC OSC Frequency R = 33KΩ 480 540 600 KHzExternal Clock Operationf EX External Frequency - 480 540 600 KHzDuty Cycle - 45 50 55 %T R ,T F Rise/Fall Time - - - 0.2 µsWrite Mode (Writing data from MPU to ST7920)T C Enable Cycle Time Pin E 1200 - - nsT PW Enable Pulse Width Pin E 140 - - nsT R ,T F Enable Rise/Fall Time Pin E - - 25 nsT AS Address Setup Time Pins: RS,RW,E 10 - - nsT AH Address Hold Time Pins: RS,RW,E 20 - - nsT DSW Data Setup Time Pins: DB0 - DB7 40 - - nsT H Data Hold Time Pins: DB0 - DB7 20 - - nsRead Mode (Reading Data from ST7920 to MPU)T C Enable Cycle Time Pin E 1200 - - nsT PW Enable Pulse Width Pin E 140 - - nsT R ,T F Enable Rise/Fall Time Pin E - - 25 nsT AS Address Setup Time Pins: RS,RW,E 10 - - nsT AH Address Hold Time Pins: RS,RW,E 20 - - nsT DDR Data Delay Time Pins: DB0 - DB7 - - 100 nsT H Data Hold Time Pins: DB0 - DB7 20 - - nsInterface Mode with LCD Driver(ST7921)T CWH Clock Pulse with High Pins: CL1, CL2 800 - - nsT CWL Clock Pulse with Low Pins: CL1, CL2 800 - - nsT CST Clock Setup Time Pins: CL1, CL2 500 - - nsT SU Data Setup Time Pin: D 300 - - nsT DH Data Hold Time Pin: D 300 - - nsT DM M Delay Time Pin: M -1000 - 1000 nsV3.1 34/42 2003/04/11