2
dc1185b-a/-bf
DEMO MANUAL
DC1185B-A/-B
QUICK START PROCEDURE
Demonstration circuit 1185 is easy to set up to evaluate
the performance of the LTC3850EUF. Refer to Figure 1
for the proper measurement equipment setup and follow
the procedure below:
Note: When measuring the output or input voltage ripple,
care must be taken to avoid a long ground lead on the
oscilloscope probe. See Figure 2 for the proper scope
probe technique. Short, stiff leads need to be soldered
to the (+) and (–) terminals of an output capacitor. The
probe’s ground ring needs to touch the (–) lead and the
probe tip needs to touch the (+) lead.
Place jumpers in the following positions:
JP1
RUN1
ON
JP2 RUN2
ON
JP3
MODE
CCM
With power off, connect the input power supply to VIN
and GND.
Turn on the power at the input.
Note: Make sure that the input voltage does not exceed 15V.
Check for the proper output voltages.
Version DC1158B-A:
V
OUT1
= 1.960V to 2.040V
V
OUT2
= 1.764V to 1.836V
Version DC1158B-B:
V
OUT1
= 1.470V to 1.530V
V
OUT2
= 1.176V to 1.224V
Once the proper output voltages are established, adjust
the loads within the operating range and observe the
output voltage regulation, ripple voltage, efficiency and
other parameters.
Note: Do not apply load across the VOS
n
+ and VOS
n
–
turrets. These turrets are only intended to Kelvin sense
the output voltage across COUT1 and COUT4. Heavy load
currents may damage the output voltage sense traces.
Figure 1. Proper Measurement Equipment Setup
