On Mar 5, 7:29, Ethan Dicks wrote:
> I'm trying to assist in the reverse
> engineering and can *not* find any data on the LED display itself, a
> MAN2815, nor one of the chips that seems to be driving it, a National
> DS8867.
> Anybody heard of these parts?
Yes :-) The MAN series used to be popular but I'm afraid I don't have
any data. However, I do have a data sheet for the DS8867 -- it gets a
page-and-a-bit in the 1980 Nat Semi Interface Data Book:
DS8867 is an 18-pin DIP 8-segment constant-current driver, designed to
be driven from MOS circuits operateing at 8V +/-10% minimum, and will
supply 14mA typical current to an LED display. Output current is not
sensitive to Vcc variations.
Features:
internal current control - no external resistors
100% efficient - no standby power
operates in 3- and 4-cell battery systems
inputs and outputs grouped for easy PC placement
Absolute maximum ratings:
Vcc 7V
input voltage 10V
output voltage 10V
Operating conditions:
Vcc min 3.3V max 6.0V
ambient temperature min 0deg C max 70deg C
logical '1' input typ 4.9V max 5.4V
logical '0' input typ 0.1uA max 10uA
logical '1' output min -8mA typ -14mA max -18mA
logical '0' output typ -0.5uA max -10uA
Pinout is straightforward, pins 1..8 are inputs 1..8, pin 9 is ground,
pins 10..17 are outputs 8..1 (ie the outputs are almost opposite the
inputs), pin 18 is Vcc.
--
Pete Peter Turnbull
Network Manager
University of York
Received on Wed Mar 05 2003 - 12:43:01 GMT