Some additional terms are defined on this slide. An Analog Front End is an analog signal conditioning circuit that uses opamps, filters, and comparators to eventually interface to an ADC. Many of the analog sensors that are used in typical applications require AFEs before prior to being input to the ADC on a microcontroller. The Balun is an electrical device that converts a differential RF signal to a single ended signal or vice versa. An Antenna Matching Network, or AMN, is an RLC circuit that provides Balun functionality. It also provides antenna impedance matching and low-pass filtering. The BLE Protocol Stack, also referred to as the Stack, is a firmware that implements the Bluetooth 4.0 or 4.1 specification to provide the layer for the BLE communication. BLE Profile, or Profile, is a Bluetooth specification that guarantees operation-level interoperability between devices that use the same profile. For example, devices such as a keyboard use a HID profile while a medical device like a heart rate monitor will use the HRM profile. All these profiles are specified by the Bluetooth low energy classification. On the bottom of the slide is a block diagram showing the various layers and the Bluetooth low energy protocol stack. It illustrates how individual parts of the stack will communicate between the Bluetooth Smart device and the Bluetooth Smart Ready device.