MGC3030 datasheet(13/50 Pages) MICROCHIP

13 / 50 page

 2012-2015 Microchip Technology Inc.

Advance Information

DS40001667D-page 13

MGC3030/3130

2.2.1.4

Approach Detection

FIGURE 3:

APPROACH DETECTION

Approach Detection is an embedded power-saving

feature of Microchip’s Colibri Suite. It sends MGC3X30

to Sleep mode and scans periodically the sensing area

to detect the presence of a human hand.

Utilizing the in-built Self Wake-up mode, Approach

Detection alternates between Sleep and Scan phases.

During the Scan phases, the approach of a human

hand can be detected while very low power is

consumed.

For

details,

please

see

Section 4.2.4.3 “Self Wake-up Mode”

A detected approach of a user exceeding configured

threshold criteria will alternate the MGC3X30 from Self

Wake-up to Processing mode or even the application

host in the overall system.

Within the Approach Detection sequence, the following

scans are performed:

• Approach Scan: An Approach scan is performed

during the scan phase of the MGC3X30’s Self

Wake-up mode. Typically, one Rx channel is

active but more channels can be activated via the

GestIC Library. The time interval (Scan Interval)

between two consecutive Approach scans is

configurable. For typical applications, the scan

cycle is in a range of 20 ms to 150 ms. During the

Approach scan, the activated Rx channels are

monitored for signal changes which are caused

by, for example, an approaching human hand and

exceeding the defined threshold. This allows an

autonomous wake-up of the MGC3X30 and host

applications at very low-power consumption.

• Calibration Scan(1): The Approach Detection

feature includes the possibility to perform

additional Calibration scans for the continuous

adaptation

the

electrode

system

environmental changes.

A Calibration scan is performed during the scan

phase of the MGC3X30’s Self Wake-up mode.

Five Rx channels are active to calibrate the

sensor signals. The Calibration scan is usually

performed in configurable intervals from 2s to

1024s.

To reduce the power consumption, the number of

scans per second can be decreased after a

certain time of non-user activity. Colibri Suite

provides a full user flexibility to configure the

starting Calibration Scans rate (Calibration Start

Scan

Interval),

non-user

activity

time-out

(Calibration Transition Time) and the Calibration

scans rate (Calibration Final Scan Interval) which

will be used afterwards. A typical implementation

uses Calibration scans every 2s during the first

two minutes, and every 10s afterwards, until an

approach is detected.

The timing sequence of the Approach Detection feature

is illustrated in Figure 2-5.

FIGURE 2-5:

APPROACH DETECTION SEQUENCE

Current

time

Periodic Approach Scans

Calibration

Scan

Periodic Approach Scans

Calibration

Scan

Periodic Approach Scans

Calibration

Scan

Periodic Approach Scans

Scan Interval

20ms-150ms

Calibration Start Scan Interval

2s-10s

Isleep = 9µA

I5CHSCAN = 20mA

I5CHSCAN: Scan Phase with 5 active RX channels: Calibration Scan

Isleep: Sleep Phase

Calibration Final Scan Interval

2s-1024s

Calibration Transition Time (Non-user activity timeout)

2s-255s

Processing

Mode

Idle Timeout

5s-1024s

Self Wake-up mode

MGC3030 датащи(PDF) 13 Page - Microchip Technology

MGC3030 датащи(HTML) 13 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50

датащи скачать

ссылки URL