ADNS-2080 Avago Technologies US Inc., ADNS-2080 Datasheet - Page 13

• Manufacturer Part Number: ADNS-2080
• Description: Low Power Wireless LED Sensor
• Manufacturer: Avago Technologies US Inc.

Specifications of ADNS-2080

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 516-2309-5

Synchronous Serial Port
The synchronous serial port is used to set and read pa-
rameters in the ADNS-2080, and to read out the motion
information. The port is a two wire serial port. The host
micro-con troller always initiates communication; the
ADNS-2080 never initiates data transfers. SCLK and SDIO
may be driven directly by a micro-controller.
The lines that comprise the SPI port:
SCLK: Clock input. It is always generated by the master
SDIO: Input/Output data.
Power Management Modes
The ADNS-2080 has three power-saving modes. Each
mode has a different motion detection period with its re-
spective response time to mouse motion. Response Time
is the time taken for the sensor to ‘wake up’ from rest mode
when motion is detected. When left idle, the sensor auto-
matically changes or downshift from Run mode to Rest1,
to Rest2 and finally to Rest3 which consumes the least cur-
rent. Do note that current consumption is the lowest at
Rest3 and highest at Rest1, however time required for sen-
sor to respond to motion from Rest1 is the shortest and
longest from Rest3. Downshift Time is the elapsed time
(under no motion condition) from current mode to the
next mode for example, it takes 10s for the sensor that is
in Rest1 to change to Rest2. The typical response time and
downshift time for each mode is shown in the following
table. However, user can change the default time setting
for each mode via register 0x0e through 0x13.
Note:
These default timings are subject to changes after characterization.
Another feature in ADNS-2080 that can be used to opti-
mize the power consumption of the optical mouse system
is the Motion Interrupt Output or MOTION pin (pin 3). It
allows the host controller to be in sleep mode (or lowest
operating current mode) when there is no motion detect-
ed after some time instead of consistently be in active
mode and polling motion data from the sensor. When
motion is detected, the sensor will send the motion inter-
rupt signal through pin 3 to the controller to wake it up
from sleep mode to resume its motion detection routine
for navigation position and direction update.
13
Mode
Rest 1
Rest 2
Rest 3
(the micro-controller).
Response Time
(Typical)
20 ms
100 ms
500 ms
Downshift Time
(Typical)
<1 s
10 s
600 s
MOTION Detection Routine
Typically in the motion detection routine, MCU will poll
the sensor for valid motion data by checking on the
MOTION_ST bit in MOTION_ST register. If MOTION_ST bit
is set, motion data in DELTA registers is valid and ready to
be read by the MCU. For 8-bit motion reporting the DELTA
registers are DELTA_X and DELTA_Y and for 12-bit motion
reporting the DELTA registers are DELTA_X, DELTA_Y and
DELTA_XY_HIGH.
MOTION Function
MOTION output signal (pin 3) can be used as interrupt in-
put to the microcontroller of the mouse to trigger the con-
troller to read the motion data from the sensor whenever
there is motion detected by the sensor. The MOTION sig-
nal can be configured to be level or edge triggered, active
high or low by setting the bits in MOTION_CTRL register.
For active high level-triggered configuration, the
MOTION pin level will be driven high as long the MOTION
bit in register 0x02 is set and there is motion data in DELTA
registers ready to be read by the microcontroller. Once
all the motion data has been read, DELTA registers value
become zero, MOTION bit is reset and the MOTION pin
level is driven low.
For active high edge-triggered configuration, a pulse of
380ns (typical) will be sent through the MOTION pin when
there is motion detected by the sensor during rest modes.
The pulse can be used as interrupt input to activate the
microcontroller from its sleep mode to enter into run
mode to start polling the sensor for motion data by moni-
toring MOTION_ST bit (set whenever there is valid motion
data) in MOTION register (0x02) and reading DELTA regis-
ters until MOTION_ST bit is reset.