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                                                                   EXHIBIT 10.11
[LOGO]

April 17, 1998

Bob Erickson
[Address]


Dear Bob,

Synplicity, Inc. is pleased to confirm our offer of regular, full-time
employment starting April 22, 1998, as Vice President of Engineering in our
Silicon Valley office. In this position, you will be reporting to Bernie
Aronson. Your primary responsibilities as Vice President of Engineering will be
managing the development and corporate applications/support groups.

Here are some details of the offer.

PAY: Your base starting pay will be equivalent to $180,000 per year. As a
professional (exempt) employee, you will be paid on a salaried basis, with
paydays occurring semi-monthly, on the fifteenth and the last business day of
each month.

If your employment is terminated without cause, Synplicity will pay you a lump
sum of six months additional base salary. "Cause" will be defined as the
determination by the CEO or the board of directors that you have refused to
follow CEO or board directives, violated your non-disclosure agreement with the
company or your duties of loyalty or care, committed a felony or an act of moral
turpitude or other action not becoming of an officer, engaged in actions which
involved gross negligence or willful misconduct in the performance of your
duties, or the like.

STOCK: It will be recommended to the Board of Directors that you receive an
Incentive Stock Option (ISO) for two hundred sixty thousand (260,000) shares of
Synplicity common stock, in accordance with the 1995 Synplicity, Inc. Stock
Option Plan, as amended. Your option price will be at the fair market value
determined by the Board of Directors at the next Board meeting held after your
hire date. All grants are contingent upon Board approval.

If all or substantially all of Synplicity's assets or outstanding shares are
sold, or if Synplicity is a party to a merger as a result of which Synplicity
shareholders do not own more than 50% of the surviving entity, and your
employment is terminated without cause (as defined herein) or constructively
terminated without cause within twelve months after such sale or merger ("Sales
Transaction"), this ISO will immediately vest for an additional twelve months.
Constructive termination will mean a resignation following a change in business
location outside the San Francisco Bay Area, a reduction in salary, or a
diminution in responsibilities such that you no longer have a role commensurate
with the position of a senior manager in charge of an engineering department
similar in size to Synplicity's.
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SIGN-ON BONUS: You will receive a one time sign-on bonus of $36,000, payable on
your first paydate.

RELOCATION EXPENSES: Synplicity will reimburse you for relocation expenses for
you and your family from Oregon to the Bay Area. Copies of your receipts are
required for reimbursement. Expenses are covered as follows: Up to $10,000 in
expenses to transport your personal belongings from Oregon to the Bay Area.

Synplicity will also provide a one-bedroom furnished apartment for the period of
four months to enable your transition.

HEALTH BENEFITS: Synplicity offers group medical, dental and vision benefits for
all full-time, regular employees effective on your hire date.

401K: Synplicity has a 401K plan. The plan has quarterly enrollment and a
partial company matching. We will provide you with details when you begin your
employment.

OTHER BENEFITS: All full-time, regular Synplicity employees receive Life
Insurance, Short Term Disability, and Travel AD&D insurance effective on your
hire date.

PAID TIME OFF (PTO): Synplicity's current policy is as follows: Synplicity
allows 15 days of paid time-off per year for vacation, sick time, doctor's
appointments, and other personal time off.

OFFICIAL HOLIDAYS: Holidays include: New Year's Day (Jan. 1); President's Day
(third Monday in February), Memorial Day (last Monday in May); Independence Day
(July 4th); Labor Day (first Monday in September); Thanksgiving day and the day
after (last Thursday & Friday in November); and, Christmas Day and the day after
(December 25/th/ & 26).

With your employment, comes the responsibility that you will honor any
confidentiality agreements you have signed with other companies. If you have any
confidential information or trade secrets, written, or otherwise known by you,
you are not to bring them to Synplicity, and you agree not to use them on the
job in any way. You attest that you have not signed a "non-competition"
agreement or any other agreement that would prohibit you from working here. This
offer is contingent upon reviewing your current confidentiality agreement at
Ambit (if any exist).

Your employment is "At Will". Both you and Synplicity agree that your employment
is completely voluntary in nature, and will not be for a specific duration or
term.
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Page 3

Bob, we are very excited about the prospect of having you as a member of the
Synplicity team and believe you will find us to offer many exciting challenges
of a small company, and a dynamic environment.

You may accept this offer by signing below and sending it back. We anxiously
await your positive acknowledgment of this employment offer and look forward to
you officially joining us here at Synplicity.

Sincerely,



/s/ Ken McElvain
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Ken McElvain, Chief Technical Officer



/s/ Bernie Aronson
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Bernie Aronson, President and CEO



/s/ Bob Erickson         4/21/98         4/22/98
----------------         -------         -------
Bob Erickson,            Today's Date    Start Date

I accept your offer of employment with all the terms and conditions described
herein, and agree to sign, on my first day, Synplicity's standard employment
confidentiality agreement. Also, by signing this agreement, I attest that I am
legally allowed to work in the United States.

This offer is valid until April 20, 1998.