VT5365

Introduction

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Care has been taken to implement ultra-low power idle/sleep modes with wakeups at

programmable periods and/or via external events, enabling very long battery life. It is

estimated that with a typical user and two AA Alkaline batteries configured in parallel, a

useful battery lifetime of 9 months can be achieved.

STMicroelectronics default firmware supports 5 buttons, mechanical Z-wheel, low battery

level detect/indicate output and internal DC/DC controller to supply the navigation LED.

The firmware generates baseband 4.8 kbps, Manchester coded data with RF on signal for

standby.

The output can be selected as either baseband RF serial data, or 27.045 MHz FSK digitally

modulated signal. In this case, minimal external circuitry is required for filtering and

amplification, and the overall system can be achieved using a single 12 MHz Xtal.

This firmware may be replaced allowing customers to build in their own features for their

particular mouse (including 2 extra GPIO). For more details please refer to Section 4:

Customizable firmware on page 16.

The VT5365 sensor will operate over a wide range of illuminant wavelengths and is suitable

for use with visible, IR and laser light sources.

A specifically designed optical system with integrated light guide and lens is available along

with an aperture piece which clips the package in place aligning the optics. This has been

optimized for low cost, space saving and ease of assembly in high volume mouse

manufacture.

The main functional blocks of the VT5365 are shown in Figure 2.

Figure 2.

VT5365 block diagram

TRK_LED

Pixel Array

365 Core

12 MHz

Buttons

Vdd (1.8 V)

LED Control

VT5365

Power

SDA

SCL

Optional

EEPROM

Power

RFON

RFOUT

X1

X0

GPIO1-7

Z-wheel

GPIO 0

LO BATT

SGPIO 0

SGPIO 1

PSU

Select

VGATE

VLED

VHIGH

27 MHz

Passive LC

1.8 V Single Stage

Amplifier

Single Cell Voltage

Management

Filter