Datasheet
FRDM-K64F Hardware Description
FRDM-K64F Freedom Module User’s Guide, User's Guide, Rev. 1, 08/2016
NXP Semiconductors 5
Table 1. FRDM-K64F power requirements
Supply source
Valid range
OpenSDAv2 operational?
Regulated onboard?
OpenSDAv2 USB
5 V
Yes
Yes
K64 USB
5 V
No
Yes
VIN Pin
5-9 V
No
Yes
3.3V Header (J20)
1.71-3.6 V
No
No
DC Jack (Not Populated)
5-9 V
No
Yes
NOTE
The OpenSDAv2 circuit is only operational when a USB cable is
connected and supplying power to OpenSDAv2 USB. However, the
protection circuitry is in place to enable multiple sources to be powered at
once.
Figure 3. Power supply schematic
Table 2. FRDM-K64F power supplies
Power supply name
Description
P5–9V_VIN
Power supplied from the V
IN
pin of the I/O headers (J3 pin 16). A Schottky diode
provides back
drive protection.
P5V_SDA_PSW
Power supplied from the OpenSDAv2 USB connector. A Schottky diode provides back drive
protection.
P5V_K64_USB
Power supplied from the K64 USB connector. A Schottky diode provides back drive protection.
DC_JACK
Power supplied from the DC Jack (not populated) connector. A Schottky diode provides back drive
protection.
P3V3_VREG
Regulated 3.3V supply. Sources power to the P3V3 supply rail through a back drive protection
Schottky diode
1
.
P3V3_K64
K64 MCU supply. Header J20 provides a convenient means for energy consumption
measurements
2
.
P3V3_SDA
OpenSDAv2 circuit supply. Header J18 provides a convenient means for energy consumption
measurements.
P5V_USB
Nominal 5 V supplied to the I/O headers (J3 pin 10).
1. By default, the linear regulator, U17, is a 3.3 V output regulator. This is a common footprint that would allow the user to
modify the assembly to utilize an alternative device, such as 1.8 V. The K64 microcontroller has an operating range of
1.71 V to 3.6 V.
2. By default, the J18 and J20 headers are populated. P3V3_K64 rail is connected with two resistors, R64 and R66. To
measure the energy consumption of the K64 MCU, the trace between J20 pin 1 and 2 must be first cut. A current probe or
shunt resistor and voltage meter can then be applied to measure the energy consumption on these rails.