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I'm looking to replace an FP2800a decoder/driver IC for a flipdot display.

This chip decodes to 28 outputs, which it can drive towards a Vcc of 30V or GND with a maximum of 300mA.

A search on distributor websites gave nothing comparable, all modern display driver ICs with internal decoder can supply a maximum of a few mA only, while switching to a design with an external decoder would give me an insane component count (and way too much current capacity).

The smallest design I can come up with at the moment would be one decoder IC driving a set of FETs that connect a half-bridge to the output -- so 30 FETs, and one readymade half-bridge driver that integrates the "high/low" and "enable" signals.

Is there a better way to do this?

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  • \$\begingroup\$ You could consider descrete array devices, perhaps such as the TC2080 or SLA5074. There are literally hundreds of variants of transistor arrays, shouldn't be too challenging to find one which will work well. \$\endgroup\$ – rdtsc Jun 18 '17 at 15:59
  • \$\begingroup\$ The datasheet shows only one output on to get the 370 mA of course. There are at least a few ways to tackle the problem depending on what your actual current requirement for the display is (you don't say). The Philips NPIC6C4894 can provide up to 250 mA sink for a 12 bit output at reasonable cost: assets.nexperia.com/documents/data-sheet/NPIC6C4894_Q100.pdf ....you could drive these with a small MCU to do parallel to serial if required. If you are designing a whole board replacement, then consider the Microchip series of HV shift registers such as the HV582. \$\endgroup\$ – Jack Creasey Jun 18 '17 at 16:03
  • \$\begingroup\$ @JackCreasey, I need to source and sink 300mA at least to drive the solenoids in the display. No need to drive multiple pins at the same time (in fact that would be annoying, as the display gives a loud click for each pixel). \$\endgroup\$ – Simon Richter Jun 18 '17 at 16:26

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