Digitimer D330 MultiStim System (D337, D330, D331, D332, D335, D333 (2), D342 (2))

MULTISTIM SYSTEM D330 SYNC&GATE D331 + PULSE D332 MODULE 

DESCRIPTION
The D332T Pulse Module provides the internal frequency and pulse width for the stimulation pulse. It provides 5 decades of control for the frequency and 4 decades for the pulse width using single turn controls and rotary switches.

• The width (duration) circuit is designed so that :-
• There is a stimulus pulse at the very start of a gating period initiated by the D331AT Sync & Gate, D341A Sync & Train or externally.
• The output pulse is always FULL WIDTH and is not terminated by the end of a gate period.
• The output pulse will not be extended if a second trigger pulse is received whilst a width pulse is in operation. A trigger pulse will be able to initiate a second FULL width pulse almost immediately after the end of the first pulse – there is no way of guarding against this, and this may look like a single double width pulse at the output.Gate input) or when an externally derived pulse is used to define stimulus duration and frequency (via the Pulse input).

The D331AT Sync & Gate Module is designed to deliver repetitive bursts of pulses. The bursts can last a set duration of time and can be repeated with a set repetition interval. If the duration time is set too long so that a second repetition command is requested during a burst, it is ignored, the requested burst duration is completed and an error is indicated.Full external control and monitoring is provided for both the gate (repetition and duration) and pulse (frequency and width) function.

The D330 MultiStim System from Digitimer has sockets that allow for external control and synchronization. Here are some details about the D330 MultiStim System's sync features:

• SYNC pulse train

A compatible trigger at the IN socket is translated into a SYNC pulse train.
The REPETITION and DURATION settings determine the pulse repetition rate and train duration.

• Delayed pulse

The DELAY dial can introduce a delayed pulse after each SYNC pulse. This delayed pulse can be detected at the OUT-1/OUT-2 output.

• Gating

The operator can gate the train of pulses on and off with an external device.

• D341 Sync & Train Module

This module allows for extra delayed pulses to be generated for studies involving refractory period.

• D332 Pulse Module

This module ensures that there is a stimulus pulse at the beginning of a gating period. The output pulse is always full width and is not terminated by the end of a gate period.

The modular MultiStim System D330 is intended to be used in labs where a variety of in vitro preparations in tissue baths or cell culture wells need field stimulation from a low impedance source. Multistim system D330 has D342 2-Channel Bi-Phasic Switcher,D335 Meter,D333H Dual Stimulator and module either SYNC,GATE,PULSE or combination.
Each channel of the system employs the same time waveform, but each preparation receives a distinct stabilized stimulus. Modules for constant voltage and constant current stimulation are part of the system.

The system offers two types of stimulation:
1.continuous current stimulation (up to 500mA from a 100V source - D343).
2.constant voltage stimulation (up to 100V at 1A-D333H). D342 2-Channel

• Bi-Phasic Switcher

This 2-Channel Bi-Phasic switcher is for use with a D333H or D343 module. The unit provides the switching function required to alternate the polarity of the stimuli to each of two preparations. It provides control of stimulus polarity (Normal, Alternating or Reverse)
independently for each channel as well as warning of a stimulus timing rate that is toofast. The control and timing for the pulses is generated by selecting other modules from the D330 - MultiStim™ range.It should be noted that the unit works with
mechanical relays that require a certain time to switch their polarity. The circuitry is designed so that the changeover command is taken (independently for each channel) from the end of each stimulus timing pulse so that the relay ‘moves’ when no stimulus is being applied.

• D335 Meter

This module allows selection of the channel for monitoring of current or voltage. This is displayed on a 3-digit display which is ‘held’ until the next pulse, for ease of reading.

• D333H Dual Stimulator

A double-width unit with two totally independent constant voltage stimulation channels. The D333H has an output capability allowing a maximum output of up to 1 A per channel.

Specifications
Polarity Selector: Normal Left hand blue socket will go positive with respect to associated right hand blue socket
                              Alt: Polarity of sockets with respect to each other reverse with each stimuli
                              Reverse: Right hand blue socket will go positive with respect to associated left hand blue socket
Amplitude: As set on associated D333H/D343 channel, optional D335 METER module will display current and voltage
Current: 1 A max. (depends on D333H/D343)
Output: Pair of 2 mm sockets (with compliance)
Mechanical Life: 100,000,000 (100 Million) operations at 10 Hz
Electrical Life: 5,000,000 operations at 200 mA, 200,000 operations at 1 A Note: only applies if stimulus rate is NOT too high (< 5 ms ISI)
Indicators: Reverse Amber LED indicates output pulse is ‘REVERSE’ Too-Fast Red LED illuminates if ‘off’ time between stimuli is < 5 msec

There several modules for the D330-MultiStim system:
D331AT Sync & Gate Module
D332T Pulse Module
D333H DualStim Module
D334B Sync Module
D335 Meter Module
D337 MultiStim Case & Power Supply
D340 Count & Delay Module
D341A Sync & Train Module
D342 Dual Bistim Module
D343 DualStim Module (Constant Current)
D344A Remote Module

Built-in Stimulus Monitoring
To precisely monitor voltage or current, the system can be equipped with the D335 - Meter. To create pulses with changeable frequency and width that can be controlled as bursts using a gating waveform with variable repetition rate, length, or pulse count, a variety of timing modules are available. There are sockets installed to provide complete external control and synchronization, if necessary.

Bench Top or Rack Mountable
The D337 19" rack-mountable unit, which houses the Gated Pulse Train Generators and up to ten stimulation channels, is a version of the D330-MultiStim System rack/case.
Because the system is modular, it can be divided into smaller components or extended to serve two sites.