Service manual

Revision 2/18/05 3 - 59
Hardware Description
Patient Signal Path - VikingQuest
The Patient Signal Path functional unit is a Nicolet-
unique part of the VikingQuest. The Least Replaceable
Units (LRUs) are designed and manufactured by
VIASYS Healthcare.
Hardware Components
The signal path functional unit consists of the following
components:
• 2-Channel Preamplifier (or)
• 4-Channel Preamplifier
• VikingQuest Base
Amplifier Block Diagram
The VikingQuest amplifier system is physically divided
between the 2- or 4-channel Preamplifier module and
the VikingQuest base board.
Electrodes from the patient plug into the preamplifier
module, which provides x10 signal amplification and
<100 MOhm common mode rejection.
The amplified patient signals are routed to the
VikingQuest base, where they are further amplified,
filtered, isolated, and processed by a 16-bit analog to
digital converter.
The filtered analog patient signals are also mixed and
presented to an audio amplifier and speaker for
listening.
VikingQuest Block Diagram
Opto
Isolators
Mixer
Power
Amplifier
DC/DC
Converter
Registers
16-Bit
ADC
Electrical
Stimulator
ES2
Option
Auditory
Stimulator
Visual
Stimulator
USB
Peripheral
Controller
Micro
Controller
USB
Hub
Control
Panel
USB
Conn.
USB
Conn.
USB
Conn.
FPGA
Mux Control
ADC Control
Registers
Trigger Out
Ext. Trigger In
Reflex Hammer In
To Computer
USB Peripherals
USB 2.0
Nicolet
S403
+--
Opto
Isolator
2nd HPF
LPF
HPF
Adj Gain
Opto
Isolator
2nd HPF
LPF
HPF
Adj Gain
Opto
Isolator
2nd HPF
LPF
HPF
Adj Gain
Opto
Isolator
2nd HPF
LPF
HPF
Adj Gain
Hybrid
Hybrid
Preamplifier
Module
Mux
ADC Timing & Control
Stim Controller
*
*
Optional Daughterboard
Isolated
Control
x10
EMG Speaker