LIMITED WARRANTY

For a period of two years following the date of delivery, CONMED Corporation warrants the CONMED System 7550 Electrosurgical Generator against any defects in material or workmanship and will repair or replace (at CONMED's option) the same without charge, provided that routine maintenance as specified in this manual has been performed using replacement parts approved by CONMED. This warranty is void if the product is used in a manner or for purposes other than intended.

525 French Road

Utica, New York 13502 U.S.A.

U.S. Patent Numbers 4,437,464 - 4,569,345 - 4,617,927 - 4,727,874 - 4,848,335 - 4,961,739 - 5,152,762 - 5,626,575 and other patents pending.

For Technical Service or Return Authorization Phone: 303-699-7600 / 1-800-552-0138 Extension 5274 Fax 303-699-1628

For Customer Service or to order parts phone: 1-800-448-6506 / 315-797-8375 / Fax 315-735-6235 or contact your CONMED Representative.

European Authorized Representative

MDSS GmbH

Burckhardtstr 1

D - 30163 Hannover

Germany

The revision level of this manual is specified by the highest revision letter found on either the inside front cover or enclosed errata pages (if any).

Manual Number 60-7552-ENG Rev. D 10/06

Unit Serial Number ___

Table of Contents List of Illustrations

Section Title Page

1.0 General Information ..... Refer to Operator's Manual (P/N 60-7551)
2.0 System Components ..... Refer to Operator's Manual
3.0 Operation ..... Refer to Operator's Manual
4.0 Operator Service ..... Refer to Operator's Manual
5.0 Technical Information ..... Refer to Operator's Manual
6.0 Circuit Descriptions ..... 6-1
6.1 Introduction ..... 6-1
6.2 Display Panel Assembly [A5] ..... 6-1
6.2.1 General Information ..... 6-1
6.2.2 Mailbox [U19] ..... 6-1
6.2.3 Power Adjustments [U16 & U33] ..... 6-1
6.2.4 Activation Requests [U16 & U33] ..... 6-2
6.2.5 Mode Select Encoders [U31 & U32] ..... 6-2
6.2.6 Display Drivers - Seven Segment [U14, U20, U39, U40, U41, & U17] ..... 6-3
6.2.7 Indicator Driver [U34] ..... 6-3
6.2.8 Firmware [U28 & U1] ..... 6-3
6.2.9 RAM [U2-6116] ..... 6-3
6.2.10 A/D Inputs [Control Microcontroller] ..... 6-3
6.2.11 A/D Inputs [Monitor Microcontroller] ..... 6-4
6.2.12 EEPROM & Driver [U37, U27] ..... 6-4
6.2.13 D/A Converter [U12] ..... 6-4
6.2.14 Keyboard Scanner [U5] ..... 6-5
6.2.15 5V Monitoring [U29] ..... 6-5
6.2.16 Output PIA [U21] ..... 6-5
6.2.17 T_MON [U35] ..... 6-5
6.3 Power Control Assembly [A4] ..... 6-5
6.3.1 Power Control - Full Bridge Amplifier ..... 6-6
6.3.2 RF Logic [U7 on the Power Control Assembly] ..... 6-7
6.3.3 Power Control - I/O Signals ..... 6-8
6.3.4 ABC™ Arc Sense ..... 6-8
6.4 High Voltage Power Supply [A7] ..... 6-9
6.4.1 Power Supply Topology ..... 6-9
6.4.2 Phase Control Output ..... 6-9
6.4.3 HVPS Isolation Components ..... 6-10
6.4.4 HVPS Low Voltage Components ..... 6-11
6.5