–

–

–

–

6

7

The overload condition is reset once the excess current draw is removed.

Supply for the module is connected through R17. This can be removed and

replaced by another supply or used to measure the current consumption of

the module.

Figure 8 shows the bottom of the board.

SW1 and SW2 connect the USB interface to the Command Data Interface

lines on the module. This allows the prototype board to be used with the

development kit software or a custom application. When in the “USB

Connected position”, the module is connected to the USB interface. The

“Header Only” position connects the module to the header.

Footprints for 0603 size resistors are on most lines so that pull-ups or

pull-downs can easily be added to the lines. The pads are connected to

V

schematic at the end of this document shows how each line is connected.

Using the Prototype Board

Snap a Carrier Board onto the socket on the Prototype Board as shown in

Figure 7.

Set the power switch (SW3) and connect a micro USB cable into the

connector at the top of the board. Plug the other end into a PC or any

USB charger. The board is powered by the USB bus. This board features

a prototyping area to facilitate the addition of application-specific circuitry.

The prototyping area contains a large area of plated through-holes so that

external circuitry can be placed on the board. The holes are set at 0.100”

on center with a 0.040” diameter, accommodating most industry-standard

SIP and DIP packages.

At the top of the prototyping area is a row connected to the 3.3V power

supply and at the bottom is a row connected to ground. External circuitry

can be interfaced to the transceiver through the breakout headers. The

numbers next to the headers correspond to the pin numbers on the Carrier

Board. Figure 5 shows the pin assignments for the Carrier Board.

The OVERLOAD LED indicates that that too much current is being pulled

from the USB bus. This is used to prevent damage to the parts or the bus.

Figure 7: Prototype Board with a Carrier Board

available for additional circuitry when plugged into a PC. If more current

is required, the user must power the board from an external supply or a

USB charger with more current capabilities, up to 1A.

Figure 8: Prototype Board Bottom Side