Monday , September 23 2019

VFD Driver Applications

Driving a Vacuum Fluorescent Character Display The following application uses a 5 x 7 40-digit VFD by Noritake. Each character is written in a single cycle since all 35 anodes (Al through A35) of the 5 x 7 matrix are pinned out. The characters (1 through 40) are scanned by …

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The SN75501C as a 32-Bit High-Voltage VFD Driver Introduction

Although designed originally for ac plasma Applications, the SN75501C can be used to drive VFDs. The SN75501C is a 32-bit high-voltage display driver. A logic diagram of the SN75501C is shown in Figure 8-63(b). When used as a VFD driver, the strobe input is grounded and the sustain input is …

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The SN75518 32-Bit VFD Driver Introduction

The most cost-effective driver for large displays with many anodes and grids is the SN75518. It is comprised of the same elements as the SN75512A, except it is 32 bits wide rather than only 12: a 32-bit serial-in, parallel-out shift register, 32 bits of parallel latches and 32 DMOS, totem-pole …

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The SN75514 High Voltage 12-Bit VFD Driver Introduction

The SN75514 (Figure 8-61) is similar to the SN75512A except it is capable of operating at up to 125 instead of 60 V. Although not limited to high density, applications, the SN75514 was designed to accommodate the specific requirements of large, high resolution (dot matrix) VF displays: high anode driver …

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The SN75513A 12-Bit VFD Driver Introduction

Figure 8-60 shows the logic symbol, logic diagram and driver output circuit of the SN75513A. The SN75513A is a 12-bit VFD driver with totem-pole outputs which minimize the required IDBT to less than 1µS. Input data is shifted into a 12-bit serial shift register on the positive transition of the …

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The SN75512A 12-Bit VFD Driver Introduction

Figure 8-59 shows a logic symbol, logic diagram and output circuit of the SN75512A. The SN75512A is a 12-bit VFD driver with totem-pole outputs. The totem-pole outputs minimize the required IDBT to less than 1µS. Input data is stored in the 12-bit serial shift register on the positive transition of …

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The UCN4810A & TL4810A 10-Bit VFD Driver Introduction

The UCN4810A 10-Bit VFD Driver Figure 8-57 shows the block diagram, logic symbol and output circuit of the UCN4810A. The UCN4810A is a 10-bit active-high VFD driver. Input data is stored in a 10-bit serial shift register on the positive transition of the clock. Parallel data is presented to the …

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Vacuum Fluorescent Displays Introduction & Construction

INTRODUCTION A vacuum fluorescent display (VFD) operates on the same basic principles as a triode vacuum tube. It is composed of a grid, cathode, and an anode that has been coated with phosphor. The anode will emit light when electrons from the cathode strike it with sufficient energy. The blue-green …

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Functional Adaptation of The SN75500A And SN75501C

In the previous text, functional waveforms were discussed. It is the intent of this section to discuss the adaptation of the SN75500A and SN75501C to these drive techniques and to identify specific considerations which must be observed for satisfactory operation.  Strobing and Sustaining  The output gate circuitry for the SN75500A …

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SN75501C AC Plasma Display Axis Driver Definition & Technology

The SN75501C is designed to generate the negative select pulses. In addition, the internal control circuitry provides for all outputs to be switched low independent of the stored data when the sustain input is taken low. This feature is provided primarily for the purpose of creating a supplemental sustain signal. …

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