User's Guide
LM940 HW Design Guide
1VV0301352 Rev. 2 Page 41 of 68 2017-07-19
Information – LM940 contains an internal pull-up resistor on SIMIO. It
is not necessary to install external pull – up resistor.
6.5.3. Control Signals
The LM940 supports the following control signals:
W_DISABLE_N
WAKE_N
WAN_LED_N
Below table lists the control signals of LM940.
Module Control Signal
PIN Signal I/O Function Type Comment
20 W_DISABLE_N I RF disable (airplane mode) 1.8V
1 WAKE_N O Host wake-up 1.8V
42 WAN_LED_N O LED control 1.8V
6.5.3.1. W_DISABLE_N
The W_DISABLE_N signal is provided to make the LM940 goes into the airplane mode:
Enter into the airplane mode: Low
Normal operating mode: High or Leave the W_DISABLE_N not connected
The W_DISABLE_N should be controlled when the LM940 to either turn on or off.
6.5.3.2. WAKE_N
The WAKE_N signal wakes the host when specific events occur.
Recommended WAKE_N connection is the following:
Recommended WAKE_N connection
LM940
WAKE_N
Opencollector
HostInput
R1
VCC