Note 11 - Stockholders' Equity	12 Months Ended
Jan. 03, 2021
Notes to Financial Statements
Stockholders' Equity Note Disclosure [Text Block]	NOTE 11-STOCKHOLDERS’ EQUITY Common and Preferred Stock As of January 3, 2021, the Company is authorized to issue 200 million shares of common stock and has 10 million shares of authorized but unissued undesignated preferred stock. Without any further vote or action by the Company’s stockholders, the Board of Directors has the authority to determine the powers, preferences, rights, qualifications, limitations or restrictions granted to or imposed upon any wholly unissued shares of undesignated preferred stock. Reverse Stock Split On December 6, 2019, the Board of Directors of the Company approved a 1-for-14 reverse stock split of the Company’s outstanding common stock, which became effective on December 23, 2019. The reverse stock split was previously approved by the Company’s shareholders in a special meeting held on November 26, 2019. At the effective time of the reverse stock split, every 14 issued and outstanding shares of common stock of the Company were automatically combined into one issued and outstanding share of common stock without any change in the par value per share. Stockholders who would have otherwise been entitled to fractional shares of common stock as a result of the reverse stock split received a cash payment in lieu of receiving fractional shares. All share, equity awards, and per share amounts contained in this Form 10-K and the accompanying Consolidated Financial Statements have been adjusted to reflect the reverse stock split for all prior periods presented. Warrants issued in connection with the May 2018 stock issuance were also adjusted to reflect the reverse stock split for all the periods presented. Issuance of Common Stock On June 22, 2020, the Company closed an underwritten public offering of 2.5 million shares of common stock, $0.001 par value per share at a price of $3.50 per share. The Company received gross proceeds from the offering of approximately $8.8 million and incurred stock issuance costs of approximately $1.1 million. Under the terms of the underwriting agreement, the Company granted the underwriter a 30-day option to purchase up to an additional 375,000 shares of common stock to cover overallotments. On July 21, 2020 the underwriter's partially exercised the option to purchase 141,733 additional shares of common stock in connection with the offering, resulting in additional gross proceeds to the Company of approximately $496,000 and incurred additional stock issuance costs of approximately $52,000. Total gross proceeds received from this offering was approximately $9.3 million and incurred total stock issuance costs of approximately $1.2 million. Net proceeds received from this offering after deducting stock issuance costs was approximately $8.1 million. On June 21, 2019, the Company closed an underwritten public offering of 1.3 million shares of common stock, $0.001 par value per share at a price of $ 7.00 per share, which included 171,429 shares issued pursuant to the underwriters’ full exercise of their over-allotment option. The Company received net proceeds from the offering of approximately $8.0 million, net of underwriter’s commission and other offering expenses paid as of the third quarter of 2019. On March 15, 2019, the Company filed a shelf registration statement on Form S-3, under which the Company may, from time to time, sell securities in one or more offerings up to a total amount of $75 million. The Company’s shelf registration statement was declared effective on March 29, 2019. In May 2018, the Company issued an aggregate of 965,251 shares of common stock, $0.001 par value and warrants to purchase up to an aggregate of 386,100 shares of common stock in an underwritten public offering. The common stock and warrants were issued in units, with each unit consisting of (i) one share of common stock and (ii) a warrant to purchase 0.40 of a share of common stock, at a price of $16.10 per Unit. The Company received total net proceeds from the offering of $13.9 million. The warrants are exercisable any time for a period of 60 months from the date of issuance on May 29, 2018, and are exercisable at an exercisable price of $19.32 per share. The estimated grant date fair value was $7.98 per warrant and was calculated based on the following assumptions used in the Black-Scholes model: expected term of 5 years, risk-free interest rate of 2.58%, expected volatility of 52.75% and expected dividend of zero. As of January 3, 2021, warrants exercisable for 386,100 shares of common stock at an exercise price of $19.32 per share remain outstanding.

Note 11 - Stockholders' Equity

12 Months Ended

Jan. 03, 2021

Stockholders' Equity Note Disclosure [Text Block]

NOTE 11-STOCKHOLDERS’ EQUITY

Common and Preferred Stock

As of January 3, 2021, the Company is authorized to issue 200 million shares of common stock and has 10 million shares of authorized but unissued undesignated preferred stock. Without any further vote or action by the Company’s stockholders, the Board of Directors has the authority to determine the powers, preferences, rights, qualifications, limitations or restrictions granted to or imposed upon any wholly unissued shares of undesignated preferred stock.

Reverse Stock Split

On December 6, 2019, the Board of Directors of the Company approved a 1-for-14 reverse stock split of the Company’s outstanding common stock, which became effective on December 23, 2019. The reverse stock split was previously approved by the Company’s shareholders in a special meeting held on November 26, 2019. At the effective time of the reverse stock split, every 14 issued and outstanding shares of common stock of the Company were automatically combined into one issued and outstanding share of common stock without any change in the par value per share. Stockholders who would have otherwise been entitled to fractional shares of common stock as a result of the reverse stock split received a cash payment in lieu of receiving fractional shares. All share, equity awards, and per share amounts contained in this Form 10-K and the accompanying Consolidated Financial Statements have been adjusted to reflect the reverse stock split for all prior periods presented. Warrants issued in connection with the May 2018 stock issuance were also adjusted to reflect the reverse stock split for all the periods presented.

Issuance of Common Stock

On June 22, 2020, the Company closed an underwritten public offering of 2.5 million shares of common stock, $0.001 par value per share at a price of $3.50 per share. The Company received gross proceeds from the offering of approximately $8.8 million and incurred stock issuance costs of approximately $1.1 million. Under the terms of the underwriting agreement, the Company granted the underwriter a 30-day option to purchase up to an additional 375,000 shares of common stock to cover overallotments. On July 21, 2020 the underwriter's partially exercised the option to purchase 141,733 additional shares of common stock in connection with the offering, resulting in additional gross proceeds to the Company of approximately $496,000 and incurred additional stock issuance costs of approximately $52,000. Total gross proceeds received from this offering was approximately $9.3 million and incurred total stock issuance costs of approximately $1.2 million. Net proceeds received from this offering after deducting stock issuance costs was approximately $8.1 million.

On June 21, 2019, the Company closed an underwritten public offering of 1.3 million shares of common stock, $0.001 par value per share at a price of $ 7.00 per share, which included 171,429 shares issued pursuant to the underwriters’ full exercise of their over-allotment option. The Company received net proceeds from the offering of approximately $8.0 million, net of underwriter’s commission and other offering expenses paid as of the third quarter of 2019.

On March 15, 2019, the Company filed a shelf registration statement on Form S-3, under which the Company may, from time to time, sell securities in one or more offerings up to a total amount of $75 million. The Company’s shelf registration statement was declared effective on March 29, 2019.

In May 2018, the Company issued an aggregate of 965,251 shares of common stock, $0.001 par value and warrants to purchase up to an aggregate of 386,100 shares of common stock in an underwritten public offering. The common stock and warrants were issued in units, with each unit consisting of (i) one share of common stock and (ii) a warrant to purchase 0.40 of a share of common stock, at a price of $16.10 per Unit. The Company received total net proceeds from the offering of $13.9 million.

The warrants are exercisable any time for a period of 60 months from the date of issuance on May 29, 2018, and are exercisable at an exercisable price of $19.32 per share. The estimated grant date fair value was $7.98 per warrant and was calculated based on the following assumptions used in the Black-Scholes model: expected term of 5 years, risk-free interest rate of 2.58%, expected volatility of 52.75% and expected dividend of zero.

As of January 3, 2021, warrants exercisable for 386,100 shares of common stock at an exercise price of $19.32 per share remain outstanding.