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3-2 Return to Section Topics 2308-900-01 Rev. A / July 2008
Section 3: Pulse Current Measurements Model 2308 Portable Device Battery/Charger Simulator User’s Manual
Overview
The power supply can perform current measurements for dynamic loads on either battery channel
(#1) or charger channel (#2). The built-in measurements include:
• Peak measured current - measures the peak (high) current of the pulse train.
• Idle measured current - measures the idle (low) current of the pulse train.
• Average transmit current - measures the average current of the pulse train.
The high, low, and average measurements of a pulse are illustrated in Figure 3-1 . The high
measurement is triggered on the rising edge of the pulse, and an integration is performed for the
time specified for the high measurement. The falling edge of the pulse triggers the low
measurement, and an integration is performed for the time specified for the low measurement. An
average measurement is triggered on the rising edge, and the integration is specified by the
average measurement time setting. Each pulse current measurement reading will trigger on the
respective edge.
Trigger level
For the various current ranges on Model 2308, to avoid false pulse detection, you can use a trigger
level of up to 5A. All pulses, noise, or other transients that are less than the set trigger level will be
ignored. The charger channel has only one trigger level range setting from 0 to 5 A. The battery
channel (#1) has four trigger level settings that are applicable when the corresponding current
range is selected: 5 A, 500 mA, 50 mA, and 5 mA. For 5 A trigger level setting, the level may be
set from 0 to 5 A. Likewise, the level may be set from 0 to 500 mA for the 500 mA trigger level
setting, 0 to 50 mA for the 50 mA trigger level setting and 0 to 5 mA for the 5 mA trigger level
setting. These settings affect the trigger level setting
when the corresponding
current range is
NOTE
Two other measurements of pulse currents are available over the bus. Pulse
current digitization and Pulse current STEP method (battery channel only) for
details.
Available current measurement range(s) are 5 A, 500 mA, 50 mA, and 5 mA on
the battery channel and 5 A on the charger channel.
Figure 3-1
Pulse current measurement
High Low
Average
High and average measurements triggered on leading edge of pulse
Low measurement triggered on falling edge of pulse