UPD8237A

The UPD8237A is designed as high performance DMA controller which is a peripheral interface circuit for microprocessor systems. It is designed to improve system performance by allowing external devices to directly transfer information to or from the system memory.

UPD8237A has twelve features. (1)Memory to memory transfers. (2)Memory block initialization. (3)Address increment or decrement. (4)Four independent DMA channels. (5)Multiple transfer modes: block, demand, single word, cascade. (6)Independent autoinitialization of all channels. (7)Enable /disable control of individual DMA requests. (8)Independent polarity control of DREQ and DACK signals. (9)End of process input for terminating transfers. (10)Software DMA requests. (11)High performance: transfers up to 1.6Mbs. (12)Directly expandable to any number of channels. That are all the main features.

Some absolute maximum ratings of UPD8237A have been concluded into several points as follow. (1)Its ambient temperature under bias would be from 0°C to +70°C. (2)Its storage temperature range would be from -65°C to +150°C. (3)Its voltage on any pin with respect to ground would be from -0.5V to +7V. (4)Its power dissipation would be 1.5W. It should be noted that stresses above those listed in absolute maximum ratings may cause permanent damage to device.

Also some DC characteristics of UPD8237A are concluded as follow. (1)Its output high voltage would be min 2.4V at Ioh=-200uA and would be min 3.3V at Ioh=-100uA. (2)Its output low voltage would be max 0.45V. (3)Its input high voltage would be min 2.0V and max Vcc+0.5V. (4)Its input low voltage would be min -0.5V and max 0.8V. (5)Its input load current would be max +/-10uA. (6)Its output leakage current would be max +/-10uA. (7)Its Vcc supply current would be typ 65mA and max 130mA at Ta=25°C and would be typ 75mA and max 150mA at Ta=0°C. And so on. If you have any question or suggestion or want to know more information please contact us for details. Thank you!