ncv7425a ON Semiconductor, ncv7425a Datasheet - Page 6

• Manufacturer Part Number: ncv7425a
• Description: Ncv7425 Lin Transceiver With Voltage Regulator And Reset Pin
• Manufacturer: ON Semiconductor

is done by EN=HIGH when TxD pin is LOW. In order not
to transmit immediately a dominant state on the bus (because
TxD = LOW), the LIN transmitter is enabled only after TxD
returns to HIGH. If STB pin is high during the
standby−to−low slope mode transition, INH pin is pulled
high. Otherwise, it stays floating.
Stand−by Mode
the NCV7425. It can also be entered from normal mode
when the EN pin is low and the stand−by pin is high. From
sleep mode it can be entered after a local wake−up or LIN
wakeup. In stand−by mode the V
supplying external components (e.g. a microcontroller)
stays active. Also the LIN receiver stays active to be able to
detect a remote wake−up via bus. The LIN transmitter is
disabled and the slave internal termination resistor of 30 kW
between LIN and V
current consumption. Only a pull−up current source
between V
a falling edge at the LIN pin (transition from recessive to
dominant) is followed by (2) a dominant level maintained
stand−by mode:
remote wake−up (LIN)
The stand−by mode is always entered after power−up of
A remote wake−up is only detected if a combination of (1)
The wake−up source is distinguished by pin RxD in the
RxD remains HIGH after power−up or local wake−up.
RxD is kept LOW until normal mode is entered after a
BB
V
Wake
and LIN is active.
BB
V
BB
Sleep Mode
LIN
BB
is disconnected in order to minimize
Detection of Local Wake−Up
40% V
BB
CC
Sleep Mode
Stand−by Mode
voltage regulator for
t
WAKE
Figure 6. Remote Wake−Up Behavior
Figure 5. Local Wake−Up Signal
Detection of Remote Wake−Up
50% V
http://onsemi.com
BB
typ.
t
6
V
Wake
BB
Sleep Mode
consumption. This mode is entered when both EN and STB
pins are LOW coming from normal mode. The internal
termination resistor of 30 kW between LIN and V
disconnected and also the V
minimize current consumption.
Wake−up
stand−by mode (see Figure 4):
stand−by mode
sleep− to stand−by mode and can be also detected when
already in standby mode.
transition from LOW to HIGH or from HIGH to LOW is
seen on the wake pin.
for a time period > t
LIN (transition from dominant to recessive) happens.
V
regulator is monitored. Whenever the regulator output falls
below V
voltage) for longer than V
60% V
CC
Sleep Mode
The Sleep Mode provides extremely low current
NCV7425 has two possibilities to wake−up from sleep or
Local wake−up: enables the transition from sleep mode to
Remote wake−up via LIN: enables the transition from
A local wake−up is only detected in sleep mode if a
In standby, normal and low−slope modes, the V
LIN dominant level
Under−voltage Detection and RSTN Pin
BB
Stand−by Mode
CC_UV_THR
Detection of Local Wake−Up
WAKE
level (typically 90% of the nominal
Stand−by Mode
and (3) again a rising edge at pin
LIN recessive level
CC_UV_deb
CC
regulator is switched off to
PC20060427.2
50% V
PC20060427.3
t
BB
(typically 5 ms), an
typ.
t
BB
CC
is