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                                                                   EXHIBIT 10.52

An agreement is made this 23RD day of MARCH 1998 by and among :

CATALYST SEMICONDUCTOR, INC ("CSI" ) a Delaware, U.S.A. corporation, having its
principle place of business at 1250 Borregas Avenue, Sunnyvale, California
94089, U.S.A. and

TRIO-TECH INTERNATIONAL PTE LTD ("TTI") having its principle place of business
at 5 Kian Teck Road, Singapore 628765

         Whereas TTI is willing to supply OKI brand wafers to CSI from third
party supplier OKI Electronics Industry Co., Ltd ("OKI") with its principle
place of business at 4-10-3 Shibaura, Minato-ku, Tokyo, 108, Japan.

         Whereas CSI is willing to purchase OKI brand wafers from TTI under the
following terms and conditions as agreed hereunder:


1.       AGREEMENT

1.1.     CSI will place orders with TTI for wafer purchases for amount not
         exceeding US $300,000 ("principal sum" as defined under clause 2.3) per
         month. Maximum total cumulative exposure to TTI shall be only US
         $900,000 with maximum credit period being three (3) months.

1.2.     In consideration for obtaining credit terms from OKI, TTI will issue a
         standby letter of credit to OKI.

1.3      TTI will then place orders with OKI for same amount of wafers as placed
         upon itself by CSI and give instructions to OKI similar shipping
         details as per CSI' s instructions.

1.4.     OKI will only ship out the wafers to CSI's designated locations upon
         TTI's instructions and upon receiving the purchase orders from TTI.

1.5.     CSI shall not in any way instruct OKI to proceed with any shipment for
         orders secured through TTI.

1.6.     OKI shall not in any case, activate shipment orders secured by TTI upon
         instructions from CSI, whether verbal or written.

1.7.     In the event that CSI gave direct instruction to OKI to ship the wafers
         and OKI obliged to such instructions, TTI shall not be responsible for
         the shipment and CSI will be liable to pay OKI for the wafers.


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1.8      CSI agrees to remain current on all other payments/invoices due to TTI
         for services rendered besides the invoices for wafer purchases. These
         services include reimbursements for advanced payment made by TTI on
         behalf of CSI, advanced payroll for CSI's employees, burn-in services,
         tape and reel services and all other business services as and when
         incurred between TTI and CSI.

2.       PAYMENT TERMS

2.1      CSI shall make payment to TTI within 90 days upon OKI's shipment of
         goods to CSI.

2.2      TTI shall only forward payment to OKI after receiving full payment
         which consists of the principal sum plus interest (as stipulated under
         clause 2.5 and 2.6) from CSI.

2.3      The principal sum includes the cost of wafer plus whatever air freight,
         handling charges, seaport charges, taxes, insurance or other expenses
         incurred in bringing the wafers to CSI's specified locations. These
         shall be stated clearly in the invoice from OKI to TTI and shall total
         up to the credit limit of US $300,000 per month or cummulative US
         $900,000 for three months.

2.4      TTI shall not be responsible for any other costs incurred besides that
         stated in OKI's invoice to TTI. Any incidental expenses or costs
         incurred will be charged to and fully responsible by CSI.

2.5      CSI will pay TTI the full payment which is the principal sum according
         to clause 2.3 above plus interest rate of 12.125 percent per annum up
         to ninety (90) days.

2.6      Interest of 2 percent per month or the highest allowable rate shall be
         charged for any outstanding receivables unpaid after the 90 days
         credit.

2.7      Should CSI's outstanding payments for all other services and goods
         provided by TTI besides the wafer products (as stipulated in clause
         1.8) exceed 30 days, TTI reserves the right to halt all wafer shipment
         and instruct OKI to halt such shipment until the invoices are paid.

3.       SECURITY

3.1      As a security to TTI, CSI shall hold a minimum of US$1 million (one
         million dollars) worth of inventory at Trio-Tech's facilities in
         Bangkok, Thailand at any point in time.

4.       DEFAULTS

4.1      In the event that CSI shall default in its payments, and not cure any
         such default within 30 days of written notification (Default date) from
         TTI, TTI shall have the following options of 4.1a or 4.1b or a
         combination of both 4.1a and 4.1b.:
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         a.       TTI will take possession of the inventories assigned to them
                  under clause 3.1 subject to the senior right of Coast Business
                  Credit.

         b.       TTI will convert all amounts due and payable to TTI to common
                  stocks of CSI, at 20 percent discount of the closing price
                  calculated based on the average of the last five (5) trading
                  days prior to default date (the "conversion price"). The
                  number of shares to be issued to TTI is determined by dividing
                  the said amount by the conversion price of CSI's common stock.

4.2      Under 4.1b., CSI must issue and TTI must receive the stock certificates
         within two (2) weeks upon TTI's demand to convert the outstanding to
         CSI common stocks. These shares must be FULLY transferable immediately
         to any party without restrictions on the date of transfer, amount, and
         category of buyers/transferees and shall be fully tradeable on the
         stock exchange. If any such restrictions remain, CSI must take the
         necessary steps to remove such restrictions before issuing the stocks
         to TTI.

4.3      TTI shall appoint a valuer to conduct a valuation of the inventory
         pledged to TTI

4.4      All valuations conducted and all charges and costs incurred to
         determine the worth and value of the inventory shall be paid by TTI.

5.       EVENTS OF DEFAULTS

5.1      The whole of the principal sum and interest thereon and any other
         moneys covenanted to be paid by CSI under this agreement shall become
         due and immediately repayable and the security hereby created shall
         become enforceable in any of the following events:

         a)       if CSI shall commit a breach of any of the agreements,
                  stipulations, terms, covenants, conditions or undertakings
                  contained in this Agreement on its part to be observed and
                  performed and in the reasonable opinion of TTI has failed to
                  remedy it within fourteen (14) days after written notice
                  served by TTI.

         b)       if CSI ceases or threatens to cease to carry on its business.

         c)       if a petition shall be presented or an order be made or a
                  resolution be passed for winding up CSI,

         d)       if a distress or execution or other process of a Court of
                  competent jurisdiction be levied upon or issued against any
                  property of CSI and such distress execution or other process
                  as the case may be is not satisfied by CSI within seven (7)
                  days from the date thereof;

         e)       if in the reasonable opinion of TTI its security hereunder is
                  in jeopardy and notice thereof is given to CSI;
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         g)       if CSI is unable to pay its debts or any statutory
                  modification or renactment thereof or suspend the payment
                  thereof or enter into any arrangement or composition with its
                  or his creditors or there is declared by any competent court
                  or authority or moratorium on the payment of indebtedness;

         h)       if any legal proceedings suit or action shall be instituted
                  against CSI or event or events has or have occurred and a
                  situation exist and after review but TTI is of the reasonable
                  opinion that this will materially affect CSI's ability to
                  repay the principal and interest thereon and or to perform its
                  or other obligations under this agreement in accordance with
                  the terms thereof;

7.       CANCELLATION OF ORDERS

7.1      Any cancellation of orders from CSI to TTI shall be made in writing and
         communicated through facsimile. TTI shall forward the same to OKI
         immediately.

7.2      If OKI in anyway, is not able to or refuse to cancel the order, CSI
         undertakes to indemnify TTI from any losses and expenses arising from
         cancellations orders from OKI by paying the full amounts so billed to
         TTI by OKI.

7.3      TTI reserves the right to bill CSI 12.125 percent interest for any
         outstanding payable for the cancelled orders and any reasonable
         administrative charges deemed appropriate by TTI for handling the
         cancelled orders.

8        WAIVER

8.1      No failure or delay on the part of TTI in exercising nor any omissions
         to exercise any right, power, privilege or remedy accruing to TTI under
         this agreement upon any default on the part of CSI shall impair any
         such right, power, privilege or remedy or be construed to be a waiver
         thereof or an acquiescence in such default, nor shall any action by TTI
         in respect of any right, power, privilege or remedy or TTI in respect
         of any other or subsequent default.

8.2      The security liabilities or obligations created by this agreement shall
         continue to be valid and binding for all purposes whatsoever
         notwithstanding:

         a)       any time or indulgence which TTI may from time to time grant
                  to CSI for the payment of moneys due to TTI or for the
                  observance or performance of any term, stipulation, covenant
                  or undertaking on the part of CSI to be observed and
                  performed:

         b)       any arrangement entered into or any composition accepted by
                  TTI modifying its rights and remedies by any alteration in the
                  obligations, terms, stipulations, covenants and undertakings
                  contained herein or by any forbearance whether as to payment
                  time performance or otherwise.
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9.       COSTS

9.1      CSI shall pay to TTI or its solicitors on demand all reasonable fees
         disbursements and expenses in connection with or incidental to this
         agreement (including but not limited to TTI's solicitor's fees and
         expenses on a solicitor and client basis) in connection with the
         negotiation, preparation, execution, stamping and registration of this
         agreement and the documents related thereto (not exceeding US $10,000
         without the prior written consent of CSI) and shall further pay to TTI
         or to its solicitors on demand all fees and expenses whatsoever
         incurred payable to TTI in the maintenance, protection and enforcement
         of its right under clauses 4.1b. and 4.2.

9.2      If obligations or any part thereof under this agreement shall be
         required to be recovered through any process of law, or if the
         obligation or any part thereof shall be placed in the hands of
         solicitors for collection, CSI shall pay (in addition to the moneys
         then due and payable hereunder) by TTI's solicitors' reasonable fees
         and any other reasonable fees and expenses incurred in respect of such
         collection.

10.      EXPENSES INCURRED BY TTI FOR AND ON BEHALF OF CSI

10.1     All moneys expended by TTI hereunder from time to time for and on
         behalf of CSI and for its account with interest thereon at the rate
         aforesaid from the date of such payment, relating to airfreight,
         handling charges, seaport charges, taxes, legal costs and reasonable
         expenses incurred in bringing in the wafers to CSI's specified
         locations shall be recoverable from CSI and shall be repaid on demand.
         In default of payment such moneys shall be deemed to form part of the
         principal and to be secured hereunder.

11.      CHANGE IN CONSTITUTION

11.1     All security (ies), agreements (s), obligation (s) given or undertaken
         by CSI shall continue to be valid and binding notwithstanding any
         change in the constitution of CSI, if a corporation, by amalgamation,
         consolidation, reconstruction, new shareholding or otherwise, and if a
         firm, by retirement, expulsion, death, admission, accession or change
         of any partners or otherwise.

12.      WITHHOLDING TAX/CONSUMPTION TAX

12.1     All payments by CSI in respect of the goods shall be made in full,
         without set-off, deductions or counterclaim and free of and without
         deduction for or on account of tax unless CSI is required by law in any
         jurisdiction to make any such payments subject to such withholdings or
         deduction, in which case CSI shall pay such additional amount to TTI as
         may be necessary in order that the actual amount received after such
         withholding and deduction shall equal the amount that would have been
         received if such withholding or deduction were not required.
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12.2     CSI shall pay in full to the appropriate taxing authority all taxes and
         charges imposed by law in any jurisdiction on CSI and/or TTI with
         regard to the credit given and promptly deliver to TTI the original or
         certified copy of each receipt evidencing such payment. CSI shall fully
         indemnify TTI from any liability with respect to the delay or failure
         by CSI to pay such taxes or charges.

13       DISCLOSURE

13.1     CSI by acceptance of this agreement hereby authorises TTI to at any
         time, disclose to any of its subsidiaries or companies and TTI's
         appointed auditors, such information about CSI, the securities given to
         TTI or any other information in connection with CSI or the arrangement
         as TTI may in its absolute discretion think fit.

14       GOVERNING LAW

14.1     This Agreement shall be construed and have effect in all respects in
         accordance with the laws of California. CSI and TTI hereby submits to
         the jurisdiction of the U.S. Courts, but such submissions shall not be
         construed so as to limit the right of TTI to commence proceedings in
         the courts of any other country.

15       NOTICE

15.1     Any notice required or permitted to be given by any of the parties
         under this agreement shall be deemed to have been given (1) at the time
         it is delivered in person, or (2), five (5) days after despatch by
         registered airmail or (3) on the business day immediately following the
         day of despatch by facsimile, sent to the other party at the following
         respective addresses or such new addresses as may from time to time be
         supplied hereunder:

         Catalyst Semiconductor Inc.
         1250 Borregas Avenue, Sunnyvale, California 94089, USA

         and

         Trio-Tech International Pte Ltd
         5 Kian Teck Road, Singapore 628765

16.      INDEMNITY

16.1     CSI hereby indemnifies and holds TTI harmless from any and all
         liability, costs,legal fees and damages by the purchase arrangement in
         this agreement .



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17.      TERM OF AGREEMENT

17.1.    This Agreement shall be and continue to be in full force and effect for
         a period of one (1) year from the date hereof unless sooner terminated
         by either party hereto. If this agreement is found to be satisfactory
         to both parties, this contract will be automatically extended from year
         to year thereafter unless notice of termination be given in writing by
         either party at least ninety (90) days prior to the termination date of
         the original or any renewal period.

18.      FORCE MAJEURE

18.1.    TTI shall not be liable for loss, damage, detention, or delay resulting
         from any cause whatsoever beyond its reasonable control or resulting
         from such things as, but not limited to, fire, flood, strike, lockout,
         civil or military authority, insurrection, riot, war, embargo,
         transportation shortage or delay, wreck, or inability to obtain the
         wafers, and delivery dates shall be extended to the extent of delays by
         any of the foregoing or similar causes.


In witness hereof, the parties have caused this Agreement by their duly
authorized representatives as of the date first written above.


TRIO-TECH INTERNATIONAL PTE LTD


/s/ Victor Ting                                     /s/ Yong Siew Wai
-----------------------------------------           ----------------------------
Victor Ting                                         Yong Siew Wai
Chief Financial Officer                             Chief Executive Officer
and Corporate Vice President                        and President

CATALYST SEMICONDUCTOR INC


/s/ Daryl Stemm                                     /s/ Radu Vanco
-----------------------------------------           ----------------------------
Daryl Stemm                                         Radu Vanco
Vice President of Finance & Administration          President and CEO
and Chief Financial Officer



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         THIS VARIATION AGREEMENT is made the 16th day of April One Thousand
Nine Hundred and Ninety-Eight (1998) Between:-

A.       CATALYST SEMICONDUCTOR, INC ("CSI") of Delaware, U.S.A. corporation,
         having its principal place of business at 1250 Borregas Avenue,
         Sunnyvale, California 94089, U.S.A. and

B.       TRIO-TECH INTERNATIONAL PTE LTD ("TTI") having its principal place of
         business at 5 Kian Teck Road, Singapore 628765

WHEREAS:

1.       CSI and TTI have entered into an agreement on 23 March 1998 in
         accordance the terms and conditions contained therein. A copy of the
         said agreement is attached hereto marked as Annex A ("supply
         agreement"). The said agreement is a back to back agreement with an
         agreement which TTI is required to enter into with OKI Electronics
         Industry Co. Ltd ("OKI") to procure the sale and supply of wafer to CSI
         ("purchase agreement"). Clause 2.1 of the purchase agreement provides
         that TTI shall only forward payment to OKI after receiving full payment
         from CSI. In consideration of TTI agreeing to vary the purchase
         agreement with OKI by deleting clause 2.1 thereof, CSI has agreed to
         enter into this variation agreement. A copy of the purchase agreement
         containing clause 2.1 is attached hereto marked as Annex B. A copy of
         the executed purchase agreement as amended by deleting clause 2.1 is
         attached hereto marked as Annex C.

2.       CSI and TTI have mutually agreed to vary the terms of the said
         agreement in accordance with the terms and conditions hereunder.

IT IS HEREBY AGREED AS FOLLOW:

1.       In consideration of TTI agreeing to vary the purchase agreement with
         OKI by deleting clause 2.1 of the purchase agreement which reads "TTI
         shall only forward payment to OKI after receiving full payment from
         CSI", CSI hereby covenant that it will make full payment of all wafers
         supplied to them by OKI regardless of any defect, damage, delay in
         delivery or any discrepancy whatsoever relating to the wafers. CSI will
         further indemnify TTI from and against all or any claim, damage or loss
         which TTI may suffer by reason of any dispute CSI may have against OKI
         in respect of the sale and supply of wafers. CSI will further hold TTI
         harmless from any liability for any defect, damage, delay in delivery
         or any discrepancy 


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         whatsoever arising from the supply of the wafers. For the avoidance of
         doubt, TTI shall be entitled and shall not be in breach of the supply
         agreement by releasing full payment to OKI of all wafers supplied by
         them notwithstanding the presence of any defect, damage, delay in
         delivery or any discrepancy whatsoever relating to the wafers.

2.       Clause 3.1 of the supply agreement refers to U.S one million dollars
         worth of "inventory at Trio-Tech's facilities in Bangkok, Thailand
         ..........." For the avoidance of doubt and for consistency, it is
         hereby clarified that reference to "inventory" shall be reference to
         "work-in-progress".

3.       Clause 4.1(a) of the supply agreement provides as follow:-

         "TTI will take possession of the inventories assigned to them under
         clause 3.1 subject to the senior right of Coast Business Credit"

         CSI is aware of the dilution of the above security. In consideration of
         TTI agreeing to vary their contract with OKI in accordance with clause
         1 above, the parties have therefore mutually agreed to vary the supply
         agreement in accordance with the terms hereunder. CSI warrants that
         they have legal title in the work in progress of the semiconductors
         which are in the custody of Trio-Tech (Bangkok) Co. Ltd in Thailand.
         CSI hereby agrees that in the event of any default by them under the
         supply agreement and in particular to the failure by CSI to make
         payment when due, TTI shall be entitled to sell, dispose or compel the
         sale of the work in progress held by Trio-Tech (Bangkok) Co. Ltd for
         the purpose of compensating them in respect of the loss sustained by
         TTI by reason of CSI's default. CSI further covenants that in the event
         that the right to sell the work in progress arises, they will do all
         that is necessary for the purpose of transferring title in the work in
         progress to any third party on the instructions of TTI and will in
         addition authorise Trio-Tech (Bangkok) Co. Ltd to assist and effect the
         sale or disposal. PROVIDED THAT, TTI shall only be entitled to sell
         such work in progress as is necessary to compensate them for their loss
         sustained by reason of CSI's default which said sum shall not exceed
         US$1 million (US one million dollars).



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         IN WITNESS WHEREOF, the parties have caused this Agreement by their
duly authorized representatives as of the date first written above.


TRIO-TECH INTERNATIONAL PTE LTD



/s/ Victor Ting                                 /s/ Yong Siew Wai
-----------------------------                   --------------------------------
Victor Ting                                     Yong Siew Wai
Chief Financial Officer                         Chief Executive Officer
and Corporate Vice President                    and President






CATALYST SEMICONDUCTOR INC





/s/ Daryl Stemm                                 /s/ Radu Vanco
-----------------------------                   --------------------------------
Daryl Stemm                                     Radu Vanco
Finance & Administration                        President and CEO
and Chief Financial Officer