Rev. 1.20

2

June 17, 2016

HT7M2126/27/36/56/76

Mode Selection

The MODE/ACT (MODE/DT) pin is used to select the Network or Stand�alone mode. When a pull�low resistor is

externally connected between the MODE/ACT (MODE/DT) pin to the ground, the Stand�alone mode is selected.

Otherwise, the Network mode is selected if a pull�high resistor or no resistor is externally on this pin.

Network Application Circuit – Network Mode

Photo transistor

150K

HT7M21xx

VDD

VSS

MODE/ACT

SCL

VDD

I²C Interface

MCU

SDA

FTS

Interface & Pin Assignment – Network Mode

Pin #

Function

Description

1

VSS

Negative power supply, GND

2

VDD

Positive power supply

3

SDA

4

SCL

5

FTS

Photo transistor signal

6

VSS

Negative power supply, GND

7

MODE/ACT

Mode Selection/Motion Detection Output

8

TP1

No connection (Test pin)

Note: When the HT7M21xx selects Network mode and the internal enable bit ACTEN is high, the MODE/ACT

pin will output a high pulse signal with a width of 30 seconds.

Stand-alone Application Circuit – Stand-alone Mode

HT7M21xx

VDD

TRO

VSS

VCC

STATUS

MODE/ACT

FTS

VDD

Photo transistor

150K