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dc1605bf
DEMO MANUAL DC1605B
Demo BoarD use cases
Let’s margin V5 and V6 high by typing a value of 1.4V and
1.1V into the respective DAC control boxes. V5 and V6
will report an OV in the GUI and on the demo board. Both
GPIO1 and GPIO2 LEDs will turn red and the dashboard
indicates an OV condition and a latched ALERT. Note the
state of HI_FAULT bits in the STATUS_WORD register.
When the GPI2 button is pushed, the GPIO1 (OV) LED is
returned to blue and the STATUS_WORD reflects the MARG
pin as well, clearing the HI_FAULT bits. We can now change
the DACs back to 1.2V and 1.0V. The OV condition is no
longer present, however ALERT (GPIO2) remains latched
low. Since the GPI1 pin is defined as a Manual Reset,
pressing this button clears the latched ALERT, turning
GPIO2 LED blue which indicates a de-asserted high state.
Apply an external supply voltage to the turret. A sensor
or other moderate source impedance voltage may be
supervised on the V
n
inputs. A battery voltage may be
supervised since the LTC2936 supply current is < 700µA.
For example, a +5V external supply may be connected to
turret V1. Notice the GPIO1 and GPIO2 LEDs turn red, indi-
cating OV and ALERT are asserted low. The V2 thresholds
need to be changed. Enter 5.5V and 4.5V for the HI and LO
threshold settings. The GPIO1 will return high and the LED
will change to blue but the GPIO2 remains low (red) since
it indicates a latched ALERT. Press the MR pushbutton on
GPI1 to release GPIO2 back high (LED blue).
USE CASE #2
The DC1605B demo board can be configured to supervise
external supply voltages. Inputs V1-V6 may be used for
this purpose. Simply move the jumper from INT to EXT
which disconnects the backside DAC, allowing an external
voltage to be applied to the LTC2936. Please ensure the
maximum ratings on the turrets are not exceeded, most
of which are 6V.
The GPI inputs may also be used to monitor external
voltages. These pins can be configured as an auxiliary
comparator (AUXC). In this mode, the GPI pin voltage is
compared to an internal 0.5V reference. Typically an external
voltage divider is provided to obtain the appropriate trip
point for the external voltage. The GPI comparators can
be mapped to one of the GPIOs to alert the system of an
overvoltage or undervoltage condition.
