Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Sep. 30, 2024	Jun. 30, 2024
Current assets
Cash and cash equivalents	$ 6,518	$ 10,442
Short-term investments	21,790	21,474
Accounts receivable	91	77
Inventory, net:
Raw materials	2,212	2,038
Work-in-process	177	66
Finished goods	309	370
Prepaid expenses and other current assets	515	261
Total current assets	31,612	34,728
Property, Plant and Equipment, Net	2,724	2,763
Operating lease assets	83	119
Other assets, net	30	30
Total assets	34,449	37,640
Liabilities, Current [Abstract]
Accounts payable	649	373
Payroll related accruals	612	1,174
Accrued expenses and other liabilities	717	754
Operating and Finance Leases, Liability, Current	149	227
Total current liabilities	2,127	2,528
Accrued expenses and other liabilities, net of current portion	194	232
Operating and Finance Leases, Liability, Noncurrent	67	73
Total liabilities	2,388	2,833
Commitments and contingencies (Note 13)
Stockholders’ equity
Convertible preferred stock, $0.001 par value, 2,500,000 shares authorized; 280,898 shares of Series D issued and outstanding at September 30, 2024 and June 30, 2024	0	0
Common stock, $0.001 par value, 250,000,000 shares authorized at September 30, 2024 and June 30, 2024, respectively; 1,712,045 shares issued at September 30, 2024 and June 30, 2024, respectively; 1,701,729 outstanding at September 30, 2024 and June 30, 2024, respectively	190,643	190,643
Treasury shares, 10,316 at September 30, 2024 and June 30, 2024, respectively	(119)	(119)
Additional paid-in capital	82,696	82,480
Accumulated deficit	(240,298)	(237,020)
Accumulated other comprehensive loss	(861)	(1,177)
Total stockholders’ equity	32,061	34,807
Total liabilities and stockholders’ equity	$ 34,449	$ 37,640