VT5365_07 STMICROELECTRONICS [STMicroelectronics], VT5365_07 Datasheet - Page 12

• Manufacturer Part Number: VT5365_07
• Description: Single chip optical/laser mouse sensor for wireless applications
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

ST default firmware
3
3.1
3.2
3.3
3.3.1
3.3.2
3.4
12/26
ST default firmware
Switches (GPIO 3 - 7)
The VT5365 supports up to 5 switch inputs with the default firmware. These switches
provide the standard mouse functions of LEFT, RIGHT and MIDDLE as well as the
advanced functions of BACK and FORWARD. The switch inputs are all active LOW. An
external pull-up resistor is required between the switch input and the VBAT (1.8 V) supply.
Scroll wheel (GPIO 1 & 2)
The VT5365 supports the use of an external mechanical shaft encoder with quadrature
outputs to act as a scroll wheel. Pull-up resistors are required between the ZA and ZB
outputs of the shaft encoder and the VBAT supply. Note that the two quadrature outputs ZA
and ZB are not interchangeable and must be connected correctly.
GPIO 0 - internal/external RF selection + low battery output
Internal/external RF selection
The state of GPIO 0 is detected at power-up:
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For more details and schematics, please refer to the STV-365-R0X user manuals.
Low battery output
After power-up, if a low battery condition is detected, GPIO 0 becomes an output that can
drive a low current LED.
If the battery goes below 0.8 V, GPIO 0 will be pulled low during RUNNING mode only (that
is, when the mouse is moving or during ZWheel/button presses), and goes to highZ in IDLE
or SLEEP modes. If the battery voltage goes above 1 V, GPIO 0 will stay highZ in all modes.
SGPIO 0 - power supply select
The VT5365 can be powered by either a single 1.8 V supply (single/parallel batteries) or a
2.0 V to 3.2 V supply (batteries in series).
Connecting SGPIO 0 to 0 V enables the direct drive, turning off the internal 1.8 V regulator.
While connecting SGPIO 0 to 1V8 allows the VT5365 to be driven at the minimal supply of
1.8 V, all internal regulators are used.
If GPIO 0 is LOW, the RF output will be baseband serial data and an external RF
modulator will be required.
However, if GPIO 0 is HIGH at power-up, the internal RF modulator will be enabled and
the output will be digitally modulated 27.045 MHz FSK. In this case, very minimal
external circuitry is required for filtering and amplification, and the overall system can
be achieved using a single 12MHz crystal.
VT5365