Converting negative matrix to binary format

I have a matrix A=[2 3 6, -7 4 2, 8 -1 3]

Apparently dec2bin(A) doesn't work.

Is there any other way I can convert it to binary format?

[sixwwwwww]

In how many bits you want to represent a binary number?

[Walter Roberson]

duplicates http://www.mathworks.co.uk/matlabcentral/answers/109131-convert-data-to-binary-and-ascii-format