Z90371

The Z90371 is designed as the dual-scan digital TV controller with some progressive double-scan applications.The Z90371 Television Controller with OSD is based on ZiLOG's Z90371 RISC processor core.The Z90371 is a second-generation, 16-bit,fractional,two's complement CMOS Digital Signal Processor (DSP).Most instructions are accomplished in a single clock cycle. This processor features a 24-bit Arithmetic Logic Unit (ALU) and a 24-bit Accumulator.The processor also contains a six-level stack and three vectored interrupts.

The absolute maximum and minimum ratings of the Z90371 are:(1)power supply voltage:0 to 7 V;(2)input voltage:-0.3 to Vcc+0.3 V;(3)output voltage:-0.3 to Vcc+0.3 V;(4)output current hign:-10 mA;(5)output current high:-100 mA;(6)output current low:20 mA;(7)operating temperature:0 to 70;(8)storage temperature:-65 to 150.

The Z90371 provides the ability to decode closed-caption transmissions;display characters on the screen;manipulate analog and digital control circuits; monitor keypad and infrared signals directly and generate OSD if the Z90371 receives vertical and horizontal synchronization signals.The FLYBACK signals from the deflection coils are fed back to the Z90371. The controller uses these signals to align its video signals with those of the normal display. If the composite video signal is not present, video synchronization is provided by the controller. In this case, the SYNC signal pins are set to be outputs.