User's Manual

CY8CKIT-042-BLE-A Bluetooth® Low Energy (BLE) Pioneer Kit Guide, Doc. # 002-11468 Rev. *A 90
Hardware
An adjustable LDO is used to output three different voltage levels (1.9 V, 3.3 V, and 5 V) to power the
module. These voltages are selected with the J16 jumper, as shown in Figure 5-1.
Figure 5-1. Schematics and Board Highlight of LDO and Power Selection Jumper
The input to the LDO can come from either the USB, the VIN pin in the Arduino header J1, or header
J9.
Note: The typical dropout voltage of the selected LDO is 0.3 V at 500-mA output current. This gives
a minimum output of 4.6 V from the input voltage of 5 V from the VBUS. This drop also considers the
voltage drop across the Schottky diode connected at the output of the LDO to protect against voltage
applied at the output terminal of the regulator. An input voltage supply over 12 V can damage the
board.