MAXIM Integrated Products, represented by Arrow Electronics , has released the MAX6922/MAX6932/MAX6933/MAX6934 vacuum-fluorescent display (VFD) drivers, which interface a multiplexed or static VFD tube to a VFD controller or a microcontroller.
The MAX6922/MAX6934 have 32 outputs, the MAX6932 has 27, and the MAX6933 has 28, all of which are rated to 76V and continuously source 40mA and sink 4mA. The outputs can also source 75mA repetitive pulses. Any output can operate as a grid or anode driver, thus simplifying layout. Well-matched, push-pull CMOS outputs allow drivers to be paralleled together to supply additional current to larger grids.
Data is input through an industry-standard, 5Mhz, 4-wire serial interface (CLK, DATA, LOAD, BLANK) that is compatible with existing VFD drivers and controllers. BLANK turns off the display and automatically put the device into shutdown mode. The display intensity may also be controlled by pulse-width modulating the BLANK input.
The MAX6922/MAX6932/MAX6934 have a DOUT pin, which allows multiple devices to be cascaded on the same serial interface. The MAX6932/MAX6933/MAX6934 have a negative grid-supply voltage input, Vss, which allows the drivers' output swing to be made bipolar to only the filament biasing, referencing it to GND.
The MAX6932/MAX6933 are available in a 36-pin SSOP package and the MAX6922/MAX6934 are available in a 44-pin PLCC package. The MAX6934 is also available in a small, 6mm x 6mm, 44-pin TQFN package. All devices operate from a 3V to 5.5V logic supply over the automotive temperature range from -40°C to +125°C.