SFH7773 Datasheet, PDF (1/23 Pages) OSRAM GmbH – (IR-LED + Proximity Sensor + Ambient Light Sensor)

SFH 7773
(IR-LED + Proximity Sensor + Ambient Light Sensor)
Application note
preliminary
1. Introduction
The SFH 7773 combines a digital ambient
light sensor and a proximity sensor (emitter
+ detector) within one package. Additionally
the sensor provides an I²C-bus interface and
an interrupt pin to connect it to an e.g.
microcontroller.
This application note describes the basic
technical features and the components
operation, allowing the user to achieve the
full functionality of the sensor. At the end a
simple software code illustrates an example
for the implementation of the SFH 7773 into
a mobile phone environment.
Please note that this guide is only a brief
introduction. For more detailed information
and the latest products and updates please
visit www.osram-os.com or contact your
local sales office to get technical assistance
during your design-in phase.
2. Applications
Typical application areas are mobile
phones, PDAs, notebooks, cameras and
other consumer products. Common tasks for
the integrated ambient light sensor are
display brightness adjustments, whereas the
proximity sensor is usually employed to
detect objects and motions. This single
component integrates several distinct
functionalities and greatly simplifies the
design-in process in consumer as well as
industrial applications. The dark black look
of the SFH 7773 makes it ideally suitable for
implementation behind a cover glass.
The ultra-low power consumption of the
SFH 7773 makes the devices especially
suited for mobile applications, where
conservation of battery power is a critical
point.
Fig. 1: Photography and orientation of the
SFH 7773.
3. The SFH 7773
The SFH 7773 (see Fig. 1) consists of an
850 nm infrared (IR) LED and an ultra-low
power ASIC which performs the signal
processing and provides the I²C-bus
interface as well as an interrupt alert
function. Additionally the ASIC contains the
two photodiodes for proximity resp. ambient
light sensing. The functional block diagram
can be found in Fig. 2. The pinning of the
devices is stated in Tab. 1. The key features
of the SFH 7773 include:
Proximity Sensor (PS)
- detection-range up to 150 mm
- optimized for the integrated 850nm emitter
- superior ambient light suppression
(> 50 klx)
- immunity to crosstalk
- fast access to PS signal
- high power (stacked) emitter version for
extended detection range are available
on request
Ambient Light Sensor (ALS)
- 0.03 lx – 65 000 lx
- excellent linearity
December 12, 2011
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