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2308-900-01 Rev. A / July 2008
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Section Topics
4-15
Model 2308 Portable Device Battery/Charger Simulator User’s Manual
Section 4: Long Integration Measurements
OFF
ON
ON
This mode allows the user to know whether the pulse disappeared before a
user-triggered reading is requested. The responsiveness of bus commands is
governed by LINT TOUT (if no pulses are detected), or by search time (if
pulses are detected). Reading time does not have to elapse after detecting the
pulse in this mode. Therefore, the longest response time to bus commands is
approximately the greater of either TOUT or search time values. Refer to
Figure 4-3
.
With DETect ON, no background long integration measurements will occur
between user-triggered readings but pulse detection occurs. If the pulse is
detected, the front panel will display DETECT on top line of display instead of
LONG INT. If no pulses are detected, the front panel will display NO DETECT
as well as the PTT (Pulse Trigger Timeout) bit being set in the status model.
Since the PTT bit is latched (see
Section 7
on Status Model), a query for the
PTT bit may indicate that pulse trigger timeout occurred although the display is
showing DETECT. The checking for the parameter of LINT TLEV commands
will occur which may set the PTT bit since looking for a rising edge. This
functionality occurs if TEDGe is set to RISING or FALLING.
If TEDGe is set to NEITHER, pulse detection will fail since synchronization to
an edge for triggering does not occur (there is nothing for the unit to detect). In
this mode, the DETECT/NO DETECT on the front panel is not reliable and the
setting of the PTT bit of the status model will not happen. Since checking for
the parameter of LINT TLEV commands to detect a pulse looks for the RISING
edge, this will occur and may set the PTT bit of the status model.
OFF
ON
OFF
With DETect OFF, background long integration measurements will occur
between user-triggered readings as well as pulse detection. If the pulse is
detected, the front panel will display LONG INT on top line of display along
with the reading on the bottom line. If no pulses are detected, the front panel
will display NO PULSE as well as the PTT (Pulse Trigger Timeout) bit being
set in the status model. Since the PTT bit is latched (see
Section 7
on Status
Model), a query for the PTT bit may indicate that pulse trigger timeout occurred
although the display is displaying LONG INT and a reading. Checking for the
parameter of LINT TLEV commands to detect a pulse occurs by looking for a
rising edge. This may set the PTT bit. If detecting pulses, the supply’s
responsiveness to bus commands is affected by search time plus reading time.
If not detecting pulses, the supply’s responsiveness to bus commands is
affected by TOUT. Therefore the longest response time to bus commands is
approximately the greater of either TOUT or search time plus reading time
(refer
Figure 4-3
). This functionality occurs if TEDGe is set to RISING or
FALLING.
If TEDGe is set to NEITHER, pulse detection will fail since synchronization to
an edge for triggering does not occur (there is nothing for the unit to detect). In
this mode, the front panel will show LONG INT on the top line with a reading on
the bottom. The user will have to determine if the pulse was present for the
reading or not. In this mode, the PTT bit of the status model will not be set as
well and therefore, not useful. Since checking the parameter of LINT TLEV
commands to detect a pulse looks for the RISING edge, this may set the PTT
bit of the status model if TLEV setting causes no rising edge pulse detection.
Table 4-3
FAST, SEARch, and DETect command reference
FAST SEARch DETect
Description
Shaded cells designate command with precedence in each mode.
Summary of Contents for 2308
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