Rev. 0.3 7/13

Copyright ©2013 by Silicon Laboratories

Si1120-EK

Si1120-EK

1. Kit Contents

The Si1120 Evaluation Kit contains the following items:

2. Introduction

The Si1120EK is intended as an evaluation and development platform for the Si1120 infrared proximity and

ambient light sensor. Two PCBs are included in the kit: the Si1120 EVB shown in Figure 1, and the C8051F930-TB

shown in Figure 2. Although the C8051F930-TB is part of the development kit, the documentation in this user’s

guide will focus on the Si1120 EVB and the example firmware. For more specific information on the C8051F930

TB, refer to the “C8051F930-DK User’s Guide”. The main components of the Si1120 EVB are the Si1120 sensor

(U1), the infrared emitters (D1 through D7), and header J1 which allows for selection between different infrared

emitters on the board. On this PCB, the infrared emitters used are OSRAM part number SFH 4650-Z. These

emitters have a power rating of 45 mW and a half-angle of 20 degrees. Other emitters with different characteristics

may also be used, depending on the specific application requirements.

The example firmware for the kit measures the infrared light energy detected by the Si1120 while each of three

infrared emitters are independently activated. The infrared light from these emitters will be reflected back to the

Si1120 by any object that is placed in proximity to the sensor. X, Y, and Z positions can be calculated from these

measurements. If no object is close enough to the board, the measured signal levels will fall below pre-determined

thresholds, and the position calculations will not update. The example firmware is intended to be used in

conjunction with the Si1120 Performance Analysis Tool to provide user feedback. In addition to calculating the

current position, the firmware is able to detect different gestures from the infrared sensor, as described in Table 1

on page 5. The Si1120’s ambient light sensor (ALS) is also monitored by the firmware, which can determine the

type of ambient light present.

Note: The touchless infrared position detection implemented in the example is patent pending.

3. Getting Started

The Si1120 Evaluation Kit requires some PC software to be installed, as well as some basic hardware setup of the

boards included in the kit.

3.1. Software Download and Installation

1. Browse to the Si1120 Evaluation Kit page at the URL http://www.silabs.com/Si1120EK.

2. Download and install the latest CP210x USB-to-UART Virtual COM Port (VCP) driver. This driver is necessary

to establish serial communications with the board.

3. Download and install the latest version of the Optical Sensors Programmer’s Toolkit. The Si1120 Performance

Analysis Tool is part of this package, and is an integral part of the example firmware functionality.

4. (Optional) Download and install the Silicon Laboratories IDE and the Si1120 Evaluation Kit package. This will

enable programming and debugging of the example source code. Note that the firmware is pre-loaded into the

board during manufacturing. The IDE and board package are needed to upgrade or modify the firmware.