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                                                                  Exhibit 10.5.1


                               SYNPLICITY, INC.

                       2000 EMPLOYEE STOCK PURCHASE PLAN

                            SUBSCRIPTION AGREEMENT


_____ Original Application                        Enrollment Date: ___________
_____ Change in Payroll Deduction Rate
_____ Change of Beneficiary(ies)

1.   ____________________ hereby elects to participate in the Synplicity, Inc.
     Employee Stock Purchase Plan (the "Employee Stock Purchase Plan") and
     subscribes to purchase shares of the Company's Common Stock in accordance
     with this Subscription Agreement and the Employee Stock Purchase Plan.

2.   I hereby authorize payroll deductions from each paycheck in the amount of
     ____% of my Compensation on each payday during the Offering Period in
     accordance with the Employee Stock Purchase Plan.  (Please note that the
     percentage withholding must be between 1% and 12% and that no fractional
     percentages are permitted.)

3.   I understand that said payroll deductions shall be accumulated for the
     purchase of shares of Common Stock at the applicable Purchase Price
     determined in accordance with the Employee Stock Purchase Plan.  I
     understand that if I do not withdraw from an Offering Period, any
     accumulated payroll deductions will be used to automatically exercise my
     option.

4.   I have received a copy of the complete Employee Stock Purchase Plan.  I
     understand that my participation in the Employee Stock Purchase Plan is in
     all respects subject to the terms of the Plan.  I understand that my
     ability to exercise the option under this Subscription Agreement is subject
     to shareholder approval of the Employee Stock Purchase Plan.

5.   Shares purchased for me under the Employee Stock Purchase Plan should be
     issued in the name(s) of (Employee or Employee and Spouse only):
     _____________________________.

6.   I understand that if I dispose of any shares received by me pursuant to the
     Plan within 2 years after the Enrollment Date (the first day of the
     Offering Period during which I purchased such shares) or one year after the
     Exercise Date, I will be treated for federal income tax purposes as having
     received ordinary income at the time of such disposition in an amount equal
     to the excess of the fair market value of the shares at the time such
     shares were purchased by me over the price which I paid for the shares.  I
                                                                              -
     hereby agree to notify the Company in writing within 30 days after the date
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     of any disposition of my shares and I will make adequate provision for
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     Federal, state or other tax withholding obligations, if any, which arise
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     upon the
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     disposition of the Common Stock.  The Company may, but will not be
     --------------------------------
     obligated to, withhold from my compensation the amount necessary to meet
     any applicable withholding obligation including any withholding necessary
     to make available to the Company any tax deductions or benefits
     attributable to sale or early disposition of Common Stock by me.  If I
     dispose of such shares at any time after the expiration of the 2-year and
     1-year holding periods, I understand that I will be treated for federal
     income tax purposes as having received income only at the time of such
     disposition, and that such income will be taxed as ordinary income only to
     the extent of an amount equal to the lesser of (1) the excess of the fair
     market value of the shares at the time of such disposition over the
     purchase price which I paid for the shares, or (2) 12% of the fair market
     value of the shares on the first day of the Offering Period.  The remainder
     of the gain, if any, recognized on such disposition will be taxed as
     capital gain.

7.   I hereby agree to be bound by the terms of the Employee Stock Purchase
     Plan.  The effectiveness of this Subscription Agreement is dependent upon
     my eligibility to participate in the Employee Stock Purchase Plan.

8.   In the event of my death, I hereby designate the following as my
     beneficiary(ies) to receive all payments and shares due me under the
     Employee Stock Purchase Plan:

     NAME:  (Please print)_____________________________________________________
                              (First)          (Middle)         (Last)

     _________________________       __________________________________________
     Relationship
                                     __________________________________________
                                     (Address)


     Employee's Social
     Security Number:                __________________________________________
     Employee's Address:             __________________________________________
                                     __________________________________________
                                     __________________________________________


I UNDERSTAND THAT THIS SUBSCRIPTION AGREEMENT SHALL REMAIN IN EFFECT THROUGHOUT
SUCCESSIVE OFFERING PERIODS UNLESS TERMINATED BY ME.

Dated:_________________________      __________________________________________
                                     Signature of Employee

                                     __________________________________________
                                     Spouse's Signature (If beneficiary other
                                     than spouse)

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                                   EXHIBIT B
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                               SYNPLICITY, INC.

                       2000 EMPLOYEE STOCK PURCHASE PLAN

                             NOTICE OF WITHDRAWAL


     The undersigned participant in the Offering Period of the Synplicity, Inc.
Employee Stock Purchase Plan which began on ____________, ______ (the
"Enrollment Date") hereby notifies the Company that he or she hereby withdraws
from the Offering Period.  He or she hereby directs the Company to pay to the
undersigned as promptly as practicable all the payroll deductions credited to
his or her account with respect to such Offering Period.  The undersigned
understands and agrees that his or her option for such Offering Period will be
automatically terminated.  The undersigned understands further that no further
payroll deductions will be made for the purchase of shares in the current
Offering Period and the undersigned shall be eligible to participate in
succeeding Offering Periods only by delivering to the Company a new Subscription
Agreement.

                                    Name and Address of Participant:

                                    ________________________________

                                    ________________________________

                                    ________________________________

                                    Signature:

                                    ________________________________

                                    Date:____________________________