ON Semiconductor NCV7425EVB User Manual

NCV7425EVB

NCV7425 LIN Transceiver
with Voltage Regulator and
Reset Pin Evaluation Board
User's Manual

http://onsemi.com

EVAL BOARD USER’S MANUAL

Introduction

This document describes the NCV7425EVB board for the
ON Semiconductor NCV7425 LIN Transceiver with
Voltage Regulator and Reset pin. The functionality and
major parameters can be evaluated with the NCV7425EVB
board.

The NCV7425 is a fully featured local interconnect
network (LIN) transceiver designed to interface between a
LIN protocol controller and the physical bus.

The NCV7425 LIN device is a member of the in-vehicle
networking (IVN) transceiver family of ON Semiconductor
that integrates a LIN v2.1 physical transceiver and a
low-drop voltage regulator. It is designed to work in harsh
automotive environment and is submitted to the TS16949
qualification flow.

Evaluation Board Features

 One-row Pin Header Connecting to all Circuit Signals

Enables Easy Insertion of the Evaluation Board into a
more Complex Application Setup. The Header can be
Alternatively Assembled either Perpendicular or
Parallel with the Board Plane

 Oscilloscope Test-points on All Circuit Signals
 Reverse Protection and Decoupling on the Main

(Battery) Supply

 Decoupling on VCC Regulator Output
 Additional Pull-up Resistor on the RSTN Open-drain

Output

 Filtering Circuit on the Switch-monitoring WAKE

Input

 On-board Local Wakeup Switch
 LIN-bus Termination and Optional ESD Protection
 Good Thermal Connection of the Circuit’s Exposed Pad

to the Bottom Ground Plane

NCV7425 Key Features

 LIN-Bus Transceiver

 LIN Compliant to Specification Revision 2.1

(Backward Compatible to Versions 2.0 and 1.3)
and SAE J2602

 Bus Voltage 45 V
 Transmission Rate up to 20 kBaud
 Integrated Slope Control for Improved EMI

Compatibility

 Protection

 Thermal Shutdown
 Indefinite Short-circuit Protection on Pins LIN

and WAKE Towards Supply and Ground

 Load Dump Protection (45 V)
 Bus Pins Protected against Transients in an

Automotive Environment

 ESD Protection Level for LIN, INH, WAKE and

Vbb up to 10 kV

 Voltage Regulator

 Two Device Versions: Output Voltage 3.3 V or 5 V

for Loads up to 150 mA

 Under-voltage Detector with a Reset Output to the

Supplied Microcontroller

 Over-current Limitation
 INH Output for Auxiliary Purposes (Switching of an

External Pull-up or Resistive Divider towards
Battery, Control of an External Voltage Regulator
etc.)

Typical Applications

 Automotive
 Industrial Network

 Semiconductor Components Industries, LLC, 2011

November, 2011 − Rev. 0

1 Publication Order Number:

EVBUM2045/D

NCV7425EVB

NCV7425 PIN CONNECTIONS

Figure 1. NCV7425EVB

Getting Started

Master/Slave Configuration

The NCV7425 evaluation board can be configured as
Master or Slave node. Furthermore, Master node LIN bus
pull-up resistance (R

) can be tied to VBB supply line or

LIN

to INH pin (See the figures below).

VBB

VBB

V

BB

LIN

GND

GND

WAKE

INH

OTP_SUP

N.C.

1

2

3

4

5

6

710

89

SOIC−16 LEAD

WIDE BODY

EXPOSED PAD

CASE 751AG

NCV7425

16

15

14

13

12

11

V

CC

RxD

TxD

RSTN

STB

EN

TEST

N.C.

The EMC immunity of the Master-node device can be
further enhanced by adding a capacitor between the LIN
output and ground (C

). The optimum value of this

LIN

capacitor is determined by the length and capacitance of the
LIN bus, the number and capacitance of Slave devices, the
pull-up resistance of all devices (Master and Slave), and the
required time constant of the system.

VBB

LIN Bus

VBB

INH

R

LIN

C

LIN

NCV7425

LIN

LIN Bus

R

LIN

C

LIN

INH

NCV7425

LIN

VBB

LIN Bus

VBB

INH

NCV7425

LIN

C

LIN

Figure 2. Master with Pull-up to VBB Figure 3. Master with Pull-up to INH Figure 4. Slave Configuration

Basic Connection

A simple LIN network configuration is shown in the
figure below. One Master and one Slave node is required
(Master/Slave Configuration).

VBAT

LIN

GND

GND

MCU

VCC

MASTER Node

MASTER

GND

MCU

VCC

SLAVE Node

SLAVE

Figure 5. NCV7425 Evaluation Setup Connection

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2

NCV7425EVB

Functional Description

The junction temperature is monitored via a thermal

shutdown circuit that switches the LIN transmitter and

Overall Functional Description

NCV7425 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
150 mA for supplying any external components
(microcontroller, CAN node, etc.).

NCV7425 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

voltage regulator off when temperature exceeds the TSD
trigger level.

NCV7425 has four operating states (normal mode, low
slope mode, stand-by mode, and sleep mode) that are
determined by the input signals EN, WAKE, STB, and TxD.

Operating States

NCV7425 provides four operating states, two modes for
normal operation with communication, one stand-by
without communication and one low power mode with very
low current consumption - see Figure 6 and Table 1.

output.

Table 1. MODE SELECTION

LIN

Mode Vcc RxD INH

Normal – Slope
(Note 1)

ON Low = Dominant State

High = Recessive State

High if STB = High
during State Transition;

Transceiver

Normal Slope ON High

Floating Otherwise

Normal – Low Slope
(Note 2)

ON Low = Dominant State

High = Recessive State

High if STB = High
during State Transition;

Low Slope ON High

Floating Otherwise

Stand-by (Note 3) ON Low after LIN Wakeup,

Floating OFF OFF Controlled by VCC

High Otherwise (Note 4)

Sleep OFF Clamped to Vcc (Note 4) Floating OFF OFF Low

1. The normal slope mode is entered when pin EN goes HIGH while TxD is in HIGH state during EN transition.

2. 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.

3. The stand-by mode is entered automatically after power-up.

4. In Stand-by and Sleep mode, the High state is achieved by internal pull-up resistor to VCC.

30 kW
on LIN

RSTN

Under-voltage

Monitor

Normal Mode

(Normal Slope)

: On

− V

CC

− LIN TRX: On

− INH: High/Floating

− LIN Term.: 30 kW

− RxD Pin: LIN Data

− RSTN Pin: High

EN Changes 1 −> 0 while STB = 0

Sleep Mode

− VCC: Off

− LIN TRX: Off

− INH: Floating

− LIN Term.: Current Source

− RxD Pin: at VCC

− RSTN Pin: Low

PD20090610.01

Vbb Power-up

Standby Mode

− VCC: On

− LIN TRX: Off

− INH: Floating

− LIN Term.: Current Source

− RxD Pin: High/Low

− RSTN Pin: VCC_UV

VCC Under-voltage

EN Changes 0 −> 1 while TxD = 0

EN Changes 1 −> 0 while STB = 1

Normal Mode

(Low Slope)

− VCC: On

− LIN TRX: On

− INH: High/Floating

− LIN Term.: 30 kW

− RxD Pin: LIN Data

− RSTN Pin: High

EN Changes 0 −> 1 while TxD = 1

EN Changes 1 −> 0 while STB = 1

VCC Under-voltage

LIN or Local Wake-up

EN Changes 1 −> 0 while STB = 0

Figure 6. NCV7425 State Diagram

Additional details of the NCV7425 operation and parameters can be found in the corresponding datasheet [1].

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NCV7425EVB

Schematic

Figure 7. NCV7425 LIN Transceiver with Voltage Regulator and Reset Pin Evaluation Board Schematic

Bill of Materials

Table 2. NCV7425 Evaluation Board Bill of Materials

Designator Description Value Footprint Manufacturer

C1 Capacitor SMD 1.0 nF CAP0805 PHYCOMP 2238 580 15623

R1, R2 Resistor SMD

R3, R5 Resistor SMD

C7 Capacitor SMD 10 nF CAP0603 EPCOS B37931K5103K60

C5 Capacitor SMD X7R

C3 Electrolytic Capacitor SMD

R4 Resistor SMD

C4 Capacitor SMD 100 nF CAP0603 KEMET C0603C104K5RAC

C2 Capacitor SMD (Optional) (Optional) CAP0805 (Optional) (Optional)

D1 Diode SMD MRA4003 SMA ON Semiconductor MRA4003T3G

D4 LIN bus ESD protection diode ESD LIN SOD323 (Optional) (Optional)

L1

J1

D2, D3 Switching Diode SMD MMSD4148 SOD123 ON Semiconductor MMSD4148T1G

U1

SCOPEGND SCOPEGND; Wire Bridge SCOPEGND SCOPEGND - -

SW1

FT1, FT2, FT3,

FT4

TP1, TP2, TP4,
TP5, TP7, TP8,

TP9, TP10,

TP11, TP12

Resistor SMD

(Optional Ferrite)

SIL HEADER 12 pins

Right Angle

LIN Transceiver with 3.3 V

or 5 V Voltage Regulator

SWITCH SMD SPNO

6x6mm

Rubber feet

12,7 x 12,7 x 5,8

Testpin 200 SER.

Hole 1.0 Black

2.0 kW 1206

0.25 W

10 kW

10 mF 10 V X7R

10 mF 50 V

33 kW

0R R0805 MULTICOMP MC 0.1W 0805 0R

HEADER 1X12 HDR1x12 MOLEX 90121-0772

NCV7425

SMD SWITCH PB300

SUPPORT FEET

TP S200 H1.0

BLACK

R1206 WELWYN WCR 1206 2K 2%

R0805 MULTICOMP MC 0.1 W 0805 1% 10K

CAP1206 KEMET C1206C106K8RAC

6.3 x 6.3 SMD NICHICON UUD1H100MCL1GS

R0805 MULTICOMP MC 0.1 W 0805 1% 33K

SOIC16_WB_

EP

FEET

12,7 x 12,7

TESTPIN2 VERO 20-2137

ON Semiconductor

TYCO

ELECTRONICS

3M SJ5018BLACK

Manufacturer Part

Number

3.3 V: NCV7425DW0R2G
5 V: NCV7425DW5R2G

FSM2JSMA

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4

PCB Drawings

Assembly Drawings

NCV7425EVB

Figure 8. NCV7425EVB PCB

Top Assembly Drawing

Composite Drawings

Figure 10. NCV7425EVB PCB

Top Composite Drawing

PCB Preview

Figure 9. NCV7425EVB PCB

Bottom Assembly Drawing

Figure 11. NCV7425EVB PCB

Bottom Composite Drawing (Mirrored)

Figure 12. NCV7425EVB PCB Top Side View Figure 13. NCV7425EVB PCB Bottom Side View

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NCV7425EVB

References

[1] On Semiconductor, NCV7425 Product Preview Revision P0, August 2011.

ON Semiconductor and are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice
to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability
arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages.
“Typical” parameters which may be provided in SCILLC data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All
operating parameters, including “Typicals” must be validated for each customer application by customer’s technical experts. SCILLC does not convey any license under its patent rights
nor the rights of others. SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications
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