POWER OF ATTORNEY

Know by all these presents that the undersigned hereby constitute and appoint
each of Ryan K. Stafford, Meenal A. Sethna, Rebekah Mihm and Hans Weinburger,
or any of them signing singly, with full power of substitution, the
undersigned's true and lawful attorney-in-fact to:

1) Prepare, execute in the undersigned's name and on the undersigned's behalf,
and submit to the U.S. Securities and Exchange Commission (the "SEC") a
Form ID, including amendments thereto, and any other documents necessary or
appropriate to obtain codes and passwords enabling the undersigned to make
electronic filings with the SEC of reports required by Section 16(a) of the
Securities Exchange Act of 1934 or any rule or regulation of the SEC;

2) Execute for and on behalf of the undersigned, in the undersigned's capacity
as an officer and or director of Littelfuse, Inc. (the "Company"), Forms 3, 4,
and 5 in accordance with Section 16(a) of the Securities Exchange Act of 1934
and the rules thereunder;

3) Do and perform any and all acts for and on behalf of the undersigned which
may be necessary or desirable to complete and execute any such Form 3, 4,
or 5, complete and execute any amendment or amendments thereto, and timely file
such form with the United States Securities and Exchange Commission and any
stock exchange or similar authority; and

4) Take any other action of any type whatsoever in connection with the foregoing
which, in the opinion of such attorney-in-fact, may be of benefit to, in the
best interest of, or legally required by, the undersigned, it being understood
that the documents executed by such attorney-in-fact on behalf of the
undersigned pursuant to this Power of Attorney shall be in such form and shall
contain such terms and conditions as such attorney-in-fact may approve in such
attorney-in-fact's discretion.

The undersigned hereby grants to each such attorney-in-fact full power and
authority to do and perform any and every act and thing whatsoever requisite,
necessary, or proper to be done in the exercise of any of the rights and powers
herein granted, as fully to all intents and purposes as the undersigned might or
could do if personally present, with full power of substitution or revocation,
hereby ratifying and confirming all that such attorney-in-fact, or such
attorney-in-fact's substitute or substitutes, shall lawfully do or cause to be
done by virtue of this power of attorney and the rights and powers herein
granted. The undersigned acknowledges that the foregoing attorneys-in-fact, in
serving in such capacity at the request of the undersigned, are not assuming,
nor is the Company assuming, any of the undersigned's responsibilities to comply
with Section 16 of the Securities Exchange Act of 1934.

This Power of Attorney shall remain in full force and effect until the
undersigned is no longer required to file Forms 3, 4, and 5 with respect to the
undersigned's holdings of and transactions in securities issued by the Company,
unless earlier revoked by the undersigned in a signed writing delivered to the
foregoing attorneys-in-fact.

IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be
executed as of this 20th day of January, 2017.

/s/ Dieter Roeder
Dieter Roeder