Unless otherwise provided by the articles of incorporation or bylaws, any action required by this title to be taken at a meeting of the directors of a bank or trust company, or any action which may be taken at any meeting of the directors or of a committee, may be taken without a meeting if a consent in writing, setting forth the action so taken, shall be signed by all of the directors, or all of the members of the committee, as the case may be. Such consent shall have the same effect as a unanimous vote.