OMO ElectronicOMO Electronic
Expand menu
Hello, Sign inMy Account
0 Cart

NCV7420D23G

P1-P3P4-P6P7-P9P10-P12P13-P15P16-P18P19-P20
NCV7420
www.onsemi.com
4
Figure 2. Typical Application Diagram
KL30
LIN−BUS
KL31
LIN
Master Node
1 nF
1kW
GND
NCV7420
Micro
controller
GND
INH
V
BB
VBAT
GND
10nF
WAKE
LIN
Slave Node
220pF
GND
Micro
controller
VBAT
GND
WAKE
10uF
V
CC V
CC
10uF
100nF
TESTOTP_ZAP
10nF
GND
INH
V
BB V
CC
TEST
OTP_ZAP
LIN
WAKE
10uF 100nF
V
CC
LIN
WAKE
EN
STB
TxD
RxD
NCV7420
EN
STB
TxD
RxD
10uF
Table 4. PIN DESCRIPTION
Pin Name Description
1 V
BB
Battery supply input
2 LIN LIN bus output/input
3 GND Ground
4 GND Ground
5 WAKE High voltage digital input pin to switch the part from sleep− to standby mode
6 INH Inhibit output
7 OTP_ZAP Supply for programming of trimming bits at factory testing, should be grounded in the application
8 TEST Digital input for factory testing, should be grounded in the application
9 EN Enable input, transceiver in normal operation mode when high
10 STB Standby mode control input
11 GND Ground
12 TxD Transmit data input, low in dominant state
13 RxD Receive data output; low in dominant state; push−pull output
14 V
CC
Supply voltage (output)
Overall Functional Description
LIN is a serial communication protocol that efficiently
supports the control of mechatronic nodes in distributed
automotive applications. The domain is class−A multiplex
buses with a single master node and a set of slave nodes.
NCV7420 is designed as a master or slave node for the
LIN communication interface with an integrated 3.3 V or
5 V voltage regulator having a current capability up to
50 mA for supplying any external components
(microcontroller).
NCV7420 contains the LIN transmitter, LIN receiver,
voltage regulator, power−on−reset (POR) circuits and
thermal shutdown (TSD). The LIN transmitter is optimized
for the maximum specified transmission speed of 20 kBaud
with EMC performance due to reduced slew rate of the LIN
output.
The junction temperature is monitored via a thermal
shutdown circuit that switches the LIN transmitter and
voltage regulator off when temperature exceeds the TSD
trigger level.
NCV7420 has four operating states (normal mode, low
slope mode, standby mode, and sleep mode) that are
determined by the input signals EN, WAKE, STB, and TxD.
Operating States
NCV7420 provides four operating states, two modes for
normal operation with communication, one standby without
communication and one low power mode with very low
current consumption. See Figure 3.
NCV7420
www.onsemi.com
5
Figure 3. State Diagram
EN goes from 0 to 1 while TxD = 0,
EN goes from 1 to 0
EN goes from 1 to 0
EN goes from 0 to 1 while TxD = 1,
EN goes from 1 to 0
Standby mode
Normal mode
(normal slope)
Sleep mode
Normal mode
(low slope)
Power off
from any mode
Local wake−up
or LIN wake−up
Note:
LIN Transmitter is “off” when
EN goes from 1 to 0
−V
CC
: “on”
−LIN TX: “off”
−Term: “current source”
−INH: “floating”
−RxD: pull−up to V
CC
/low
−V
CC
: “on”
−LIN TX: “on”
−Term: 30 kW
−INH: “high”/“floating”
−RxD: LIN Data (push−pull)
−V
CC
: “off”
−LIN TX: “off”
−Term: “current source”
−INH: “floating”
−RxD: pull−up to V
CC
−V
CC
: “on”
−LIN TX: “on”
−Term: 30 kW
−INH: “high”/“floating”
−RxD: LIN data (push−pull)
while STB = 0 and V
BB
> V
BB_UV_th
Power up V
BB
V
BB
> V
BB_UV_th
V
BB
< V
BB_UV_th
V
BB
< PORL_V
BB
while STB = 1 or V
BB
< V
BB_UV_th
and V
CC
> V
CC_UV_th
and V
BB
> V
BB_UV_th
while STB = 0 and V
BB
> V
BB_UV_th
and V
CC
> V
CC_UV_th
, V
BB
> V
BB_UV_th
while STB = 1 or V
BB
< V
BB_UV_th
Table 5. MODE SELECTION
Mode V
CC
RxD INH LIN
30 kW on LIN
Note
Normal −
Slope
ON Low = Dominant State
High = Recessive State
High if STB=High during state
transition; Floating otherwise
Normal
Slope
ON (Note 7)
Normal −
Low Slope
ON Low = Dominant State
High = Recessive State
High if STB=High during state
transition; Floating otherwise
Low Slope ON (Note 8)
Standby ON Low after LIN wake−up,
high otherwise
Floating OFF OFF (Notes 9
and 10)
Sleep OFF Clamped to V
CC
Floating OFF OFF
7. The normal slope mode is entered when pin EN goes HIGH while TxD is in HIGH state during EN transition.
8. The low slope mode is entered when pin EN goes HIGH while TxD is in LOW state during EN transition. LIN transmitter gets on only after
TxD returns to high after the state transition.
9. The standby mode is entered automatically after power−up.
10.In standby mode, RxD High state is achieved by internal pull-up resistor to V
CC
.
Normal Slope Mode
In normal slope mode the transceiver can transmit and
receive data via LIN bus with speed up to 20 kBaud. The
transmit data stream of the LIN protocol is present on the
TxD pin and converted by the transmitter into a LIN bus
signal with controlled slew rate to minimize EMC emission.
The receiver consists of the comparator that has a threshold
with hysteresis in respect to the supply voltage and an input
filter to remove bus noise. The LIN output is pulled HIGH
via an internal 30 kW pull-up resistor. For master
applications it is needed to put an external 1 kW resistor with
a serial diode between LIN and V
BB
(or INH). See Figure 2.
The mode selection is done by EN=HIGH when TxD pin is
HIGH. If STB pin is high during the standby-to-normal
slope mode transition, INH pin is pulled high. Otherwise, it
stays floating.
Low Slope Mode
In low slope mode the slew rate of the signal on the LIN
bus is reduced (rising and falling edges of the LIN bus signal
are longer). This further reduces the EMC emission. As a
consequence the maximum speed on the LIN bus is reduced
up to 10 kBaud. This mode is suited for applications where
the communication speed is not critical. The mode selection
is done by EN=HIGH when TxD pin is LOW. In order not
to transmit immediately a dominant state on the bus (because
NCV7420
www.onsemi.com
6
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.
Standby Mode
The standby mode is always entered after power−up of the
NCV7420. It can also be entered from normal mode when
the EN pin is low and the standby pin is high. From sleep
mode it can be entered after a local wake−up or LIN
wake−up. In standby mode the V
CC
voltage regulator for
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
BB
is disconnected in order to minimize
current consumption. Only a pull−up current source
between V
BB
and LIN is active.
Sleep Mode
The Sleep Mode provides extreme low current
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
BB
is
disconnected and also the V
CC
regulator is switched off to
minimize current consumption.
Wake−up
NCV7420 has two possibilities to wake−up from sleep or
standby mode (see Figure 3):
• Local wake−up: enables the transition from sleep mode
to standby mode
• Remote wake−up via LIN: enables the transition from
sleep− to standby mode and can be also detected when
already in standby mode.
A local wake−up is only detected in sleep mode if a
transition from LOW to HIGH or from HIGH to LOW is
seen on the WAKE pin.
Wake
t
V
BB
Detection of Local Wake−Up
Sleep Mode Standby Mode
50% V
BB
typ.
Wake
t
V
BB
Detection of Local Wake−Up
Sleep Mode Standby Mode
50% V
BB
typ.
Figure 4. Local Wake−up Signal
A remote wake−up is only detected if a combination of (1)
a falling edge at the LIN pin (transition from recessive to
dominant) is followed by (2) a dominant level maintained
for a time period > t
WAKE
and (3) again a rising edge at pin
LIN (transition from dominant to recessive) happens.
LIN recessive level
LIN
t
t
WAKE
Detection of Remote Wake−Up
V
BB
Sleep Mode Standby Mode
LIN dominant level
Figure 5. Remote Wake−up Behavior
40% V
BB
60% V
BB
The wake−up source is distinguished by pin RxD in the
standby mode:
• RxD remains HIGH after power−up or local wake−up.
• RxD is kept LOW until normal mode is entered after a
remote wake−up (LIN).
P1-P3P4-P6P7-P9P10-P12P13-P15P16-P18P19-P20

NCV7420D23G

Mfr. #:
Buy NCV7420D23G
Manufacturer:
ON Semiconductor
Description:
LIN Transceivers LIN TRANSC. 3.3V Voltage Regulator
Lifecycle:
New from this manufacturer.
Delivery:
DHL FedEx Ups TNT EMS
Payment:
T/T Paypal Visa MoneyGram Western Union

Products related to this Datasheet