User's Manual

Rev: e
© 2030 Free2move AB
Page 34(45)
Extended range Bluetooth
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Module - F2M03GXA
Datasheet
5.7 Power supply
The power supply for the F2M03GXA should be chosen carefully. Bad power supply can reduce the
performance and may damage the module. Please use the recommended voltage regulator or consult
Free2move if using another regulator. It is also essential to use a proper reset circuit to the module for
correct operation.
5.7.1 Voltage regulator
The F2M03GXA have two power supplies, +V_PA and +VCC.
It is recommended to use two separate voltage regulators for best performance but it is possible to use only
one regulator if the design is made carefully. The voltage supplied should have low noise, less than 10mV
rms between 0 and 10MHz. The transient response of the regulator is also important. At the start of a
Bluetooth packet, power consumption will jump to high levels. The regulator should have a response time of
20µs or less; it is essential that the power rail recovers quickly.
+V_PA is feeding the external PA and is in need of high current with low noise.
+VCC is feeding the internal circuits (Bluetooth chip and memory).
The power supply for +V_PA and +VCC should have less than 10mV rms noise levels between 0 to
10MHz. The recommended voltage regulator is: TPS73633DBVTG4 from Texas Instrument
5.7.2 Reset
The F2M03GXA has an active low reset (pin nr: 35).The reset pin MUST be connected to either a reset-
circuit (voltage monitor) such as the TC1270ASVRCTR, MAX811S, DS1818 or using an I/O from a
microcontroller. Reset cannot be done with a R-C network. It is recommended to used one of the reset
circuits mentioned above. Special considerations must be taken when using an I/O from a microcontroller; a
pull-down resistor (1.8kΩ) must be placed on the I/O-line.
It is recommended that RESET is applied for a period greater than 5ms.
At reset the digital I/O pins are set to inputs for bi-directional pins and outputs are tristated. The PIOs have
weak pull-downs.