HV78

The HV78 is a low-voltage serial to high-voltage parallel converter with push-pull outputs. This device has been designed for use as a driver for electroluminescent displays. It can also be used in any application requiring multiple output high-voltage current sourcing and sinking capability such as driving plasma panels, vacuum fluorescent displays, or large matrix LCD displays. The device HV78 has 2 parallel 32-bit shift registers, permitting data rates 2X the speed of one (they are clocked together). There are also 64 latches and control logic to perform the polarity select and blanking of the outputs. HVOUT1 is connected to the first stage of the first shift register through the polarity and blanking logic. Data is shifted through the shift registers on the logic low to high transition of the clock. The DIR pin causes COW shifting when connected to GND, and CW shifting when connected to VDD. A data output buffer is provided by HV78 for cascading devices. This output reflects the current status of the last bit of the shift register (HVOUTS4). Opgation of the shift reg$ is not affected by the HE (latch enable), BL (blanking), or the POL (polarity) inputs. Trans-E of data from the shift registers to the latches occurs when the LE (lag enable) input is high. The data in the latches is stored
when LE is low.

The features of HV78 can be summarized as (1)processed with HVCMOS technology; (2)5V CMOS logic; (3)output voltages up to 80V; (4)low power level shifting; (5)source/sink current minimum 15ma; (6)16MHz equivalent data rate; (7)latched data outputs; (8)forward and reverse shifting options (DIR pin); (9)diode to VPP allows efficient power recovery; (10)outputs may be hot switched; (11)Hi-Rel processing available.

The absolute maximum ratings of HV78 are (1)supply voltage, VDD: -0.5V to +7.5V; (2)supply voltage, VPP: -0.5V to +90V; (3)logic input levels: -0.3V to VDD +0.3V; (4)ground currents: 1.5A; (5)continuous total power dissipationt ceramic: 1500mW/Plastic: 1200mW; (6)lead temperature 1.6mm from case for 10 seconds: 260°C; (7)storage temperature range: -65°C to 150°C; (8) operating temperature range: 0°C to 85°C.