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Table 2. Indicators and jumpers (continued)
Circuit ref (Rev E)
Description
Default
Reference
position 2-3 when external power
supply (J24) is used.
JP12
Voltage/supply selector for i.MX
RT685
VDDIO_1 power
domain.
Selects between PMIC output
LDO2_OUT
(position 2-3) or
SW2_OUT
(position 1-2). The PMIC is
programmed to default to
SW2_OUT
at
1.8V and
LDO2_OUT
at 3.3 V, but can
be re-programmed on-the-fly by the
i.MX RT685.
1-2
SW2_OUT
1.8 V
Schematic
JP13
Host ISP control selection. This
header/jumper can be used to select
which of the Port 1 pin 15 (ISP0) or
pin 16 (ISP1) signals is routed to the
Interrupt/ISP pin on the PMod/Host
connector. These signals from can be
used as GPIO/interrupts to/from the
i.MX RT685, and may be used to
determine its boot mode following
reset.
Header is not installed
by default, but position
1-2 is shorted to select
ISP1/P1-16.
Schematic
JP14
Reset enable/disable to Arduino.
Install jumper to route the i.MX
RT685 reset control signal to the
standard Arduino reset pin.
Open
Schematic
JP15
Power supply to FXOS8700CQ
accelerometer. Connects 3.3 V from
linear regulator U25 to the
accelerometer 3.3 V supply input.
The I/O voltage for this device is
connected to the
VDDIO_1
supply rail of
the i.MX RT685.
Closed
Schematic
JP16
On button control to PMIC. Set as
directed by NXP.
1-2
Schematic
JP17, JP18, JP19
SWD port isolation jumpers. When
using the VCOM port and an external
debug probe, remove these jumpers
to prevent contention with the on-
board debug probe (LPC432x
device).
All closed
Schematic
JP20
VDDIO_0
supply connection to PMIC /
external supply injection. This jumper
is provided for optional insertion of an
ammeter to measure supply current
Closed
Table continues on the next page...
NXP Semiconductors
Board layout and settings
i.MX RT685 Evaluation Board, Rev. 0, March 20 2020
User's Guide
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