Pulse Monitor Ttl Mode - Newport 6100 User Manual

Principles of Operation
Signals Connector is driven to ground. In these exceptions, the TTL Output
signal will be HIGH to indicate that the unit is capable of supplying output
current without the normal 3-second safety-delay.
6.5.4

PULSE MONITOR TTL Mode

In PULSE MONITOR mode allows the user to synchronize external
instrumentation to the laser diode output current pulses when the unit is in
GATED, TRIGGERED, RETRIG, or FREE RUN pulse mode.
When the output current is enabled in these modes, TTL Output signal will
be HIGH when unit is supplying current and LOW when it is not. The state
of the TTL Output signal is not specified in ALWAYS ON pulse mode; it is
also not specified if the output current is disabled.
6.5.5 TTL INPUT MONITOR TTL Mode
In TTL INPUT MONITOR TTL mode, logic level present on the TTL Input
signal is buffered and output on the TTL Output signal.
6.6 LIV Characterization
For fast LIV characterization, with measurements every 10 ms, use HWCONFIG
The Model 6100 supports a data acquisition engine that enables users to
perform LIV characterization of laser diodes with relative ease. The users
can define their desired start and end output current values, number of
measurements and the dwell time at each current step. Once the LIV
characterization process is enabled, the unit starts to increase/decrease the
output current based on these setup parameters. At every current step it
measures and stores internally the following four (4) parameters: current
setpoint, measured current, forward voltage and analog control input voltage.
The unit is capable of storing up to 100 such measurement sets. Users can
retrieve these measurements from the unit via USB interface for further
analysis. The unit is designed to take a measurement every 10 ms. By default,
the data is averaged over a period of 500 ms, which is suitable for most
applications. If the user needs to perform fast LIV characterizations, the raw
data taken at every 10 ms can be made available via USB. For this, the user
needs to set bit 2 in the configuration register to 1. By default, this bit is 0.
(See the HWCONFIG command in Section 5.5)
By measuring analog control input voltage at the same time as current
setpoint, measured current and forward voltage, the unit enables users to truly
NOTE
command to set bit 2 of the configuration register to 1.
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