20-Output, 76V, Serial-Interfaced VFD Tube Drivers

The MAX6921/MAX6931 are 20-output, 76V, vacuum-fluorescent display (VFD) tube drivers that interface a multiplexed VFD tube to a VFD controller, such as the MAX6850–MAX6853, or to a microcontroller. The MAX6921/MAX6931 are also ideal for driving static VFD tubes or telecom relays.

Data is input using an industry standard 4-wire serial interface (CLOCK, DATA, LOAD, BLANK), compatibile with either Maxim's or industry-standard VFD driver and controller.

For easy display control, the active-high BLANK input forces all driver outputs low, turning the display off, and automatically puts the MAX6921/MAX6931 into shutdown mode. Display intensity can also be controlled by directly pulse-width modulating the BLANK input.

The MAX6921 has a serial interface data output, DOUT, allowing any number of devices to be cascaded on the same serial interface.

The MAX6931 has a negative supply voltage input, VSS, allowing the drivers' output swing to be made bipolar to simplify filament biasing in many applications.

The MAX6921 is available in 28-pin TSSOP, SO, and PLCC packages. The MAX6931 is available in a 28-pin TSSOP package.

Maxim also offers 12-output VFD drivers (MAX6920) and 32-output VFD drivers (MAX6922/MAX6932).

Applications

* Automotive * Avionics * Gaming Machines * Industrial Control * Industrial Weighing * Instrumentation * Security * Telecom * VFD Modules * White Goods

* 5MHz Industry-Standard 4-Wire Serial Interface

* 3V to 5.5V Logic Supply Range

* 8V to 76V Grid/Anode Supply Range

* -11V to 0V Filament Bias Supply (MAX6931 Only)

* Push-Pull CMOS High-Voltage Outputs

* Outputs can Source 40mA, Sink 4mA Continuously

* Outputs can Source 75mA Repetitive Pulses

* Outputs can be Paralleled for Higher Current Drive

* Any Output can be Used as a Grid or an Anode Driver

* Blank Input Simplifies PWM Intensity Control

* Small 28-Pin TSSOP Package

* -40°C to +125°C Temperature Range