MAXIM MAX13020, MAX13021 User Manual

General Description

The MAX13020/MAX13021 ±60V fault-protected low­power local interconnect network (LIN) transceivers are
ideal for use in automotive network applications where
high reliability is required. The devices provide the
interface between the LIN master/slave protocol con­troller, and the physical bus described in the LIN 2.0
specification package and SAE J2602 specification.
The devices are intended for in-vehicle subnetworks
with a single master and multiple slaves.

The extended fault-protected voltage range of ±60V on
the LIN bus line allows for use in +12V, +24V, and
+42V automotive applications. The devices allow com­munication up to 20kbaud, and include slew-rate limit­ed transmitters for enhanced electromagnetic
emissions (EME) performance. The devices feature a
low-power 4µA sleep mode and provide wake-up
source detection.

The MAX13020 is a pin-to-pin replacement and is func­tionally compatible with the Philips TJA1020. The
MAX13021 includes enhanced bus dominant clamping
fault management for reduced quiescent current during
LIN bus shorts to GND. The MAX13020/MAX13021 are
available in the 8-pin SO package, and operate over
the -40°C to +125°C automotive temperature range.

Applications

+12V/+42V Automotive

+24V Heavy Truck and Bus

Features

♦ MAX13020 is a Pin-to-Pin Upgrade for TJA1020
♦ ESD Protection

±12kV Human Body Model (LIN)
±4kV Contact Discharge (LIN, NWAKE, BAT)

♦ LIN 2.0/SAE J2602 Compatible
♦ Slew-Rate Limited Transmitter for Low

Electromagnetic Emissions (EME)

♦ Robust Electromagnetic Immunity (EMI)
♦ Passive Behavior in Unpowered State
♦ TXD Dominant Timeout Function
♦ LIN Bus Dominant Management (MAX13021 Only)
♦ Input Levels Compatible with +3.3V and +5V

Controllers

♦ Integrated 30kΩ Termination Resistor for Slave

Applications

♦ Low 4µA Sleep Mode with Local and Remote

Wake-Up Detection

♦ Wake-Up Source Recognition
♦ Thermal Shutdown

MAX13020/MAX13021

±60V Fault-Protected LIN Transceivers

________________________________________________________________ Maxim Integrated Products 1

19-0559; Rev 1; 6/06

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

Ordering Information

PART

L IN B U S

D O M IN A N T

PIN-

PACKAGE

CODE

MAX13020ASA+

— 8 SO S8-5

MAX13021ASA+

Yes 8 SO S8-5

BAT

TXD

RXD

NSLP

LIN

GND

INH

NWAKE

MICROCONTROLLER

LIN
BUS

1kΩ

V

BAT

MASTER NODE

ONLY

+5V LDO

*

EN

MAX5023

MAX13020
MAX13021

*OPTIONAL TXD PULLUP RESISTOR FOR READING WAKE-UP SOURCE FLAG

Typical Operating Circuit

Note: All devices are specified over the -40°C to +125°C auto­motive temperature range.
+Denotes lead-free package.

Pin Configuration appears at end of data sheet.

M A N A G EM EN T

PACKAGE

MAX13020/MAX13021

±60V Fault-Protected LIN Transceivers

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.

(All voltages referenced to GND, unless otherwise noted.
Positive currents flow into the device.)

BAT.........................................................................-0.3V to +40V

TXD, RXD, NSLP.......................................................-0.3V to +7V

LIN ...........................................................0V to ±60V Continuous

LIN to BAT..........................................................-80V Continuous

NWAKE...................................................................-0.3V to +80V

NWAKE Current (NWAKE < -0.3V) ....................................-15mA

INH ..............................................................-0.3V to V

BAT

+ 0.3V

INH Current .......................................................-50mA to +15mA

Continuous Power Dissipation

8-Pin SO (derate 5.9mW/°C above +70°C)...................471mW

Operating Temperature Range .........................-40°C to +125°C

Storage Temperature Range .............................-65°C to +150°C

Junction Temperature......................................................+150°C

Lead Temperature (soldering, 10s) ................................+300°C

ELECTRICAL CHARACTERISTICS

(V

BAT

= +5V to +38V, TA= -40°C to +125°C, unless otherwise noted. Typical values are at V

BAT

= +12V and TA= +25°C. Positive

currents flow into the device.)

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

BAT Supply Voltage V

BAT

Operating range 5.0

V

V

BAT

= +27V,

V

LIN

= V

BAT

148

Sleep mode,
V

NWAKE

= V

BAT,

V

BAT

= +38V,

V

LIN

= V

BAT

8

Standby mode, bus recessive,
V

BAT

= +5V to +27V,

V

LIN

= V

INH

= V

NWAKE

= V

BAT,

V

TXD

= V

NSLP

= GND

Standby mode, bus dominant,
V

BAT

= +12V, V

INH

= V

NWAKE

= V

BAT,

V

LIN

= V

TXD

= V

NSLP

= GND

Normal/low slope mode,
bus recessive, V

BAT

= +5V to +27V,

V

LIN

= V

INH

= V

NWAKE

= V

BAT,

V

TXD

= V

NSLP

= +5V

µA

Normal/low slope mode,
bus dominant, no load,
V

BAT

= V

INH

= V

NWAKE

= +12V,

V

TXD

= GND, V

NSLP

= +5V

1 4.5 8 mA

Sleep mode, bus dominant,
V

BAT

= V

NWAKE

= +12V,

V

LIN

= V

TXD

= V

NSLP

= GND

90

Fault mode, bus dominant (MAX13021),
V

INH

= V

NWAKE

= V

BAT

,

V

LIN

= GND, V

NSLP

= +5V

30 60

BAT Supply Current I

BAT

Disable mode, bus dominant (MAX13021),

20 30

µA

38.0

V

TXD

= V

NSLP

= GND

V

= V

BA T

IN H

= V

N WAK E

= + 12V , V

= G N D

LI N

100 650 1000

300 1000 2000

100 650 1000

MAX13020/MAX13021

±60V Fault-Protected LIN Transceivers

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(V

BAT

= +5V to +38V, TA= -40°C to +125°C, unless otherwise noted. Typical values are at V

BAT

= +12V and TA= +25°C. Positive

currents flow into the device.)

PARAMETER SYMBOL CONDITIONS

UNITS

TRANSMITTER DATA INPUT (TXD)

High-Level Input Voltage V

IH

Output recessive 2 V

Low-Level Input Voltage V

IL

Output dominant 0.8 V

Pulldown Resistance R

TXD

kΩ

Low-Level Input Current I

IL

V

TXD

= GND -5 0 +5 µA

Low-Level Output Current I

OL

Standby mode, V

NWAKE

= GND,

V

LIN

= V

BAT

, V

TXD

= +0.4V,

local wake-up request

1.5 6 mA

RECEIVER DATA OUTPUT (RXD)

Low-Level Output Current I

OL

V

LIN

= GND, V

RXD

= +0.4V 1.2 4.1 mA

High-Level Leakage Current I

LH

Normal/low slope mode,
V

LIN

= V

BAT

, V

RXD

= +5V

-5 0 +5 µA

NSLP INPUT

High-Level Input Voltage V

IH

2V

Low-Level Input Voltage V

IL

0.8 V

Pulldown Resistance R

NSLP

V

NSLP

= +5V

kΩ

Low-Level Input Current I

IL

V

NSLP

= GND -5 0 +5 µA

NWAKE INPUT

High-Level Input Voltage V

IH

V

BAT

- 1.0 V

Low-Level Input Voltage V

IL

V

NWAKE Pullup Current I

IL

V

NWAKE

= GND -30

-3 µA

High-Level Leakage Current I

LH

V

NWAKE

= +38V, V

BAT

= +38V -5 0 +5 µA

INH OUTPUT

Switch On-Resistance Between
BAT and INH

R

SW

S tand b y, nor m al /l ow sl op e m od es, I

IN H

=

- 15m A, V

BAT

= + 12V

22 50 Ω

High-Level Leakage Current I

LH

Sleep mode,
V

NWAKE

= +38V, V

BAT

= +38V

-5 0 +5 µA

LIN BUS I/O

LIN Recessive Output Voltage

)

V

TXD

= +5V, I

LIN

= -1µA V

BAT

-1.0V V

LIN Dominant Output Voltage V

O(DOM)

Normal/low slope mode,
V

TXD

= GND, V

BAT

= +7V to +27V,

R

TERM

= 500Ω to BAT

V

MIN TYP MAX

125 330 800

125 330 800

-10

V

V

O(RECES

0.2 x V

BAT

- 3.3

BAT

MAX13020/MAX13021

±60V Fault-Protected LIN Transceivers

4 _______________________________________________________________________________________

ELECTRICAL CHARACTERISTICS (continued)

(V

BAT

= +5V to +38V, TA= -40°C to +125°C, unless otherwise noted. Typical values are at V

BAT

= +12V and TA= +25°C. Positive

currents flow into the device.)

PARAMETER SYMBOL CONDITIONS

MIN

TYP

MAX

UNITS

High-Level Leakage Current I

LH

V

LIN

= V

BAT

, V

TXD

= +5V -5 0 +5 µA

Device Leakage Current, V

BAT

Disconnected

I

L(BAT)

V

BAT

= GND, V

LIN

= +18V -5 0 +5 µA

Device Leakage Current, GND
Disconnected

I

L(GND)

V

BAT

= GND, V

LIN

= -18V

0µA

LIN Current After Short Detection

I

IL(FAULT)

Fault mode, disable mode (MAX13021)
V

LIN

= GND

-10 -2 µA

Short-Circuit Recovery Threshold
Voltage

)

Fault mode, disable mode (MAX13021)

V

BAT

-

2.5

V

BAT

-

0.9

V

LIN Pullup Current I

IL

-10 -2 µA

Slave Termination Resistance to
V

BAT

R

SLAVE

S tand b y, nor m al /l ow sl op e m od es, V

LIN

=

GN D , V

BAT

= + 12V

20 30 47 kΩ

V

LIN

= V

BAT

= +12V,

V

TXD

= GND, t < t

DOM

27 40 60

V

LIN

= +12V, V

BAT

= +27V,

V

TXD

= GND, t < t

DOM

(Note 1)

45 70 100

Short-Circuit Output Current I

O(SC)

t < t

DOM

45

mA

Receiver Dominant State V

th(DOM)

V

BAT

= +7V to +38V

V

Receiver Recessive State V

th(REC)

V

BAT

= +7V to +38V 0.6 x V

BAT

V

Receiver-Threshold Center
Voltage

)

V

BAT

= +7V to +38V

0.475 x

0.5 x

0.525 x
V

Receiver-Threshold Hysteresis
Voltage

V

th(HYS)

V

BAT

= +7V to +38V

0.145 x

0.16 x

0.175 x
V

Thermal-Shutdown Threshold T

SHDN

°C

Thermal-Shutdown Hysteresis 10 °C

ESD PROTECTION

Human Body Model LIN

kV

Contact Discharge
IEC61000-4-2

LIN, NWAKE, BAT
(tested to IBEE test setup)
C

1

= 100nF on V

BAT

,

C

2

= 220pF on LIN,

R = 33kΩ on NWAKE

±4 kV

V

th(RECOVERY

-100

Sleep mode, V

= GND, V

LIN

NSLP

= GND

V

= +12V, V

BAT

= +60V, V

LIN

V

th(CENTER

= GND,

TXD

V

V

BAT

BAT

V

V

+165

±12

0.4 x V

BAT

BAT

BAT

V

BAT

V

BAT

MAX13020/MAX13021

±60V Fault-Protected LIN Transceivers

_______________________________________________________________________________________ 5

TIMING CHARACTERISTICS

(V

BAT

= +5V to +38V, TA= -40°C to +125°C, unless otherwise noted. Typical values are at V

BAT

= +12V and TA= +25°C. Positive

currents flow into the device.)

PARAMETER SYMBOL CONDITIONS

UNITS

LIN Duty Factor 1
D1 = t

BUS(REC)(MAX)

/(2 x t

BIT

)

D1

V

BAT

= +7V to +18V, V

th(REC)(MAX)

=

0.744 x V

BAT,

V

th(DOM)(MAX)

= 0.581 x V

BAT,

t

BIT

= 50µs (Figure 4, Note 2)

—

LIN Duty Factor 2
D2 = t

BUS(REC)(MAX)

/(2 x t

BIT

)

D2

V

BAT

= +8V to +18V,

V

th(REC)(MIN)

= 0.422 x V

BAT,

V

th(DOM)(MIN)

= 0.284 x V

BAT,

t

BIT

= 50µs (Figure 4, Note 2)

—

LIN Duty Factor 3
D3 = t

BUS(REC)(MAX)

/(2 x t

BIT

)

D3

V

BAT

= +7V to +18V,

V

th(REC)(MAX)

= 0.778 x V

BAT,

V

th(DOM)(MAX)

= 0.616 x V

BAT,

t

BIT

= 96µs (Figure 4, Note 2)

—

LIN Duty Factor 4
D4 = t

BUS(REC)(MAX)

/(2 x t

BIT

)

D4

V

th(REC)(MIN)

= 0.389 x V

BAT,

V

th(DOM)(MIN)

= 0.251 x V

BAT

,

V

BAT

= +8V to +18V,

t

BIT

= 96µs (Figure 4, Note 2)

—

Propagation Delay of Receiving
Node

t

p(RX)

V

BAT

= +7V to +18V,

C

RXD

= 20pF (Figure 4)

6µs

Receiver Propagation Delay
Symmetry

t

p(RX)(SYM)

V

BAT

= +7V to +18V,

C

RXD

= 20pF, R

RXD

= 1kΩ

-2 +2 µs

Continuously Dominant-Clamped
LIN Bus Detection Time

)

Normal/low slope mode (MAX13021),
V

LIN

= GND

40 80

ms

Continuously Dominant-Clamped
LIN Bus Recovery Time

)

Normal/low slope mode (MAX13021),
V

LIN

= GND

0.5 1 2 ms

Dominant Time for Wake-Up of
the LIN Transceiver

t

BUS

Sleep mode (Figure 3) 30 70

µs

TXD Permanent Dominant
Disable Time

)

Normal/low slope mode,
V

TXD

= GND

20 80 ms

Dominant Time for Wake-Up
Through NWAKE

t

NWAKE

Sleep mode 7 20 50 µs

Rising edge with respect to falling edge,

t

LIN(DOM)(DET

t

LIN(DOM)(REC

t

TXD(DOM)(DIS

MIN TYP MAX

0.396

0.581

0.417

0.590

160

150

MAX13020/MAX13021

±60V Fault-Protected LIN Transceivers

6 _______________________________________________________________________________________

TIMING CHARACTERISTICS (continued)

(V

BAT

= +5V to +38V, TA= -40°C to +125°C, unless otherwise noted. Typical values are at V

BAT

= +12V and TA= +25°C. Positive

currents flow into the device.)

PARAMETER SYMBOL CONDITIONS

MIN

TYP

MAX

UNITS

Mode Change Time from
Sleep/Standby Mode to
Normal/Low Slope Mode

(Note 3) 2 5 10 µs

Mode Change Time from
Normal/Low Slope Mode to Sleep
Mode

(Note 4) 2 5 10 µs

Note 1: Guaranteed by design for V

BAT

= V

LIN

= +27V.

Note 2: Selected bit time, t

BIT

= 50µs or 96µs (20kbaud or 10.4kbaud). Bus load conditions (C

BUS

/ R

BUS

): 1nF/1kΩ, 6.8nF/660Ω,

10nF/500Ω.

Note 3: t

GOTONORM

is measured from rising edge of N

SLP

to RXD active.

Note 4: t

GOTOSLEEP

is measured from falling edge of N

SLP

to RXD high impedance.

0

2

1

5

4

3

6

7

9

8

10

-40 -10 5-25 203550658095110125

SUPPLY CURRENT

vs. TEMPERATURE

MAX13020 toc01

TEMPERATURE (°C)

SUPPLY CURRENT (mA)

SLEEP MODE
V

LIN

= V

BAT

V

BAT

= +38V

V

BAT

= +12V

0

5

25

40

50

OPERATING CURRENT
vs. SUPPLY VOLTAGE

MAX13020 toc02

SUPPLY VOLTAGE (V)

OPERATING CURRENT (mA)

5202510 15 30 35 40

LOW SLOPE MODE

10.4kbps

NORMAL SLOPE MODE
20kbps

RL = 500Ω
C

L

= 10nF

RL = 1000Ω
C

L

= 1nF

45

10

35

30

20

15

0

10

5

20

15

25

30

021345

SINK CURRENT vs. RXD OUTPUT

LOW VOLTAGE

MAX13020 toc03

RXD OUTPUT LOW VOLTAGE (V)

SINK CURRENT (mA)

TA = +125°C

TA = +25°C

TA = -40°C

Typical Operating Characteristics

(V

BAT

= +12V and TA= +25°C, unless otherwise noted.)

t

GOTONORM

t

GOTOSLEEP

MAX13020/MAX13021

±60V Fault-Protected LIN Transceivers

_______________________________________________________________________________________ 7

0

15

10

5

20

25

30

35

40

45

50

021345

SINK CURRENT vs. TXD PULLDOWN

OUTPUT VOLTAGE

MAX13020 toc04

OUTPUT LOW VOLTAGE (V)

SINK CURRENT (mA)

TA = +125°C

TA = +25°C

TA = -40°C

STANDBY MODE
AFTER A LOCAL

0

10

5

25

20

15

30

35

45

40

50

-40 -10 5-25 203550658095110125

INH ON-RESISTANCE

vs. TEMPERATURE

MAX13020 toc05

TEMPERATURE (°C)

INH ON-RESISTANCE (Ω)

I

SINK

= 15mA

V

BAT

= +38V

V

BAT

= +12V

0

20

10

50

40

30

60

70

90

80

100

-40 -10 5-25 20 35 50 65 80 95 110 125

I

BAT

FAULT CURRENT

vs. TEMPERATURE

MAX13020 toc06

TEMPERATURE (°C)

I

BAT

FAULT CURRENT (µA)

MAX13020
V

BAT

= +12V

SLEEP MODE
V

LIN

= 0V

10µs/div

2.5MHz/div

LIN OUTPUT SPECTRUM

LIN
5V/div

FFT
20dB/div

MAX13020 toc07

RL = 660Ω
C

L

= 6.8nF
NORMAL SCOPE MODE
20kbps

20µs/div

2.5MHz/div

LIN OUTPUT SPECTRUM

LIN
5V/div

FFT
20dB/div

MAX13020 toc08

RL = 660Ω
C

L

= 6.8nF

LOW SCOPE MODE

10.4kbps

20µs/div

LIN TRANSMITTING NORMAL

SLOPE MODE

TX
5V/div

RX
5V/div

MAX13020 toc09

RL = 1kΩ
C

L

= 1nF
NORMAL SCOPE MODE
20kbps

LIN

5V/div

Typical Operating Characteristics (continued)

(V

BAT

= +12V and TA= +25°C, unless otherwise noted.)

MAX13020/MAX13021

±60V Fault-Protected LIN Transceivers

8 _______________________________________________________________________________________

Typical Operating Characteristics (continued)

(V

BAT

= +12V and TA= +25°C, unless otherwise noted.)

10µs/div

LIN TRANSMITTING NORMAL

SLOPE MODE

TX
5V/div

RX
5V/div

MAX13020 toc10

RL = 660kΩ
C

L

= 6.8nF
NORMAL SCOPE MODE
20kbps

LIN

5V/div

10µs/div

TX
5V/div

RX
5V/div

MAX13020 toc11

RL = 500kΩ
C

L

= 10nF
NORMAL SCOPE MODE
20kbps

LIN

5V/div

LIN TRANSMITTING NORMAL

SLOPE MODE

20µs/div

TX
5V/div

RX
5V/div

MAX13020 toc12

RL = 1kΩ
C

L

= 1nF
LOW SCOPE MODE

10.4kbps

LIN

5V/div

LIN TRANSMITTING LOW

SLOPE MODE

20µs/div

TX
5V/div

RX
5V/div

MAX13020 toc13

RL = 660kΩ
C

L

= 6.8nF

LOW SCOPE MODE

10.4kbps

LIN

5V/div

LIN TRANSMITTING LOW

SLOPE MODE

20µs/div

TX
5V/div

RX
5V/div

MAX13020 toc14

RL = 500kΩ
C

L

= 10nF

LOW SCOPE MODE

10.4kbps

LIN

5V/div

LIN TRANSMITTING LOW

SLOPE MODE

Detailed Description

The MAX13020/MAX13021 ±60V fault-protected low­power local interconnect network (LIN) transceivers are
ideal for use in automotive network applications where
high reliability is required. The devices provide the
interface between the LIN master/slave protocol con­troller and the physical bus described in the LIN 2.0
specification package and SAE J2602 specification.
The devices are intended for in-vehicle subnetworks
with a single master and multiple slaves.

The extended fault-protected voltage range of ±60V on
the LIN bus line allows for use in +12V, +24V, and
+42V automotive applications. The devices allow com­munication up to 20kbaud, and include slew-rate limit­ed transmitters for enhanced electromagnetic
emissions (EME) performance. The devices feature a
low-power 4µA sleep mode and provide wake-up
source detection.

The MAX13020 is a pin-to-pin replacement and is func­tionally compatible with the Philips TJA1020. The
MAX13021 includes enhanced bus dominant clamping
fault-management for reduced quiescent current during
LIN bus shorts to GND.

Operating Modes

The MAX13020/MAX13021 provide two different trans­mitting modes, an intermediate standby mode and a
low-power sleep mode. Normal slope mode allows full­speed communication at 20kbaud with a slew-limited
transmitter to reduce EME. Low slope mode permits
communication up to 10.4kbaud, and provides addi-

tional slew-rate limiting to further reduce EME. The
transmitting operating mode is selected by the logic
state of NSLP and TXD (Table 1). To enter normal slope
mode or low slope mode, drive TXD logic-high or logic­low, then drive NSLP logic-high for longer than
t

GOTONORM

. The MAX13021 features two additional
operating modes to reduce current consumption during
LIN bus shorts to GND.

On initial power-up, the device enters sleep mode.

MAX13020/MAX13021

±60V Fault-Protected LIN Transceivers

_______________________________________________________________________________________ 9

Pin Description

PIN NAME FUNCTION

1 RXD

Data Receive Output, Open Drain. RXD is logic-low when the LIN bus is dominant. RXD is active low after
a wake-up event from sleep mode.

2 NSLP S l eep Inp ut. D r i ve N S LP l og i c- hi g h or l og i c- l ow to contr ol the op er ati ng m od e. ( S ee Tab l e 1 and Fi g ur es 1, 2)

3

Local Wake-Up Input. Present a falling edge on NWAKE to generate a local wake-up event. Connect
NWAKE to BAT with a 5kΩ resistor if local wake-up is not required.

4 TXD

Data Transmit Input, CMOS Compatible. Drive TXD logic-low to force the LIN bus to a dominant state in
normal/low slope mode.

5 GND Ground

6 LIN

LIN Bus I/O. LIN is terminated with an internal 30kΩ resistor in normal slope, low slope, and standby
modes.

7 BAT

Battery Voltage Input. Bypass BAT to ground with a 0.1µF ceramic capacitor as close to the device as
possible.

8 INH Inhibit Output. INH is active high in standby and normal/low slope modes. (See Table 1)

Figure 1. MAX13020 Operating Modes

NWAKE

t

(t

= 0 AFTER 1 TO 0) > t

NWAKE

t

(LIN = 0 AFTER 1 TO 0)

t

(NSLP = 0 AFTER 1 TO 0)

(NSLP = 1 AFTER 0 TO 1)

> t

GOTONORM

TXD = 1

OR

>t

BUS

> t

GOTOSLEEP

t

(NSLP = 1 AFTER 0 TO 1)

> t

GOTONORM

TXD = 0

NWAKE

STANDBY MODE

t

(NSLP = 1 AFTER 0 TO 1)

> t

GOTONORM

TXD = 0

LOW SLOPE MODE

NORMAL SLOPE MODE

t

(NSLP = 1 AFTER 0 TO 1)

> t

GOTONORM

TXD = 1

t

(NSLP = 0 AFTER 1 TO 0)

SLEEP MODE

POWER-ON STATE

> t

GOTOSLEEP

INITIAL

MAX13020/MAX13021

Sleep Mode

Sleep mode is the lowest power operating mode and is
the default state after power is applied to BAT. In sleep
mode, the MAX13020/MAX13021 disable the LIN trans­mitter and receiver to reduce power consumption. RXD
and INH are high impedance. The internal slave termi­nation resistor between LIN and BAT is disabled, and
only a weak pullup from LIN to BAT is enabled. While in
sleep mode, the MAX13020/MAX13021 transition to
standby mode when a local or remote wake-up event is
detected. For applications with a continuously powered
microprocessor, drive NSLP logic-high for longer than
t

GOTONORM

to force the MAX13020/MAX13021 directly
into normal slope mode if TXD is logic-high, and low
slope mode if TXD is logic-low. From normal slope or
low slope mode, drive NSLP logic-low for longer than
t

GOTOSLEEP

to force the MAX13020/MAX13021 into

sleep mode.

Standby Mode

In standby mode, the LIN transmitter and receiver are
disabled, the internal slave termination resistor between
LIN and BAT is enabled, and the INH output is pulled
high. The MAX13020/MAX13021 transition to standby
mode from sleep mode when a wake-up event is
detected. From standby mode, drive TXD logic-high or
logic-low, then drive NSLP logic-high for longer than
t

GOTONORM

to transition to normal slope or low slope

mode. In standby mode, RXD is driven logic-low to
transmit the wake-up interrupt flag to a microcontroller.
The wake-up source flag is presented on TXD as a
strong pulldown in the case of a local wake-up. In the
case of a remote wake-up, TXD is pulled low by the
internal 330kΩ resistor only. The wake-up interrupt and
wake-up source flag are cleared when the
MAX13020/MAX13021 transition to normal slope mode
or low slope mode.

Normal Slope Mode

In normal slope mode, the MAX13020/MAX13021 pro­vide the physical layer interface to a LIN bus through
RXD and TXD. INH is pulled high and the internal slave
termination resistance from LIN to BAT is enabled. Data
presented on TXD is transmitted on the LIN bus with a
controlled slew rate to limit EME. Drive TXD logic-low to
assert a dominant state on LIN. The LIN bus state is
presented on the open-drain output RXD. A dominant
LIN state produces a logic-low on RXD. From standby
or sleep mode, drive TXD logic-high, then drive NSLP
logic-high for longer than t

GOTONORM

to enter normal
slope mode. Drive NSLP logic-low for longer than
t

GOTOSLEEP

to force the device into sleep mode from

normal slope mode.

±60V Fault-Protected LIN Transceivers

10 ______________________________________________________________________________________

NORMAL SLOPE MODE

FAULT MODE

LOW SLOPE MODE

SLEEP MODE

t

(NSLP = 1 AFTER 0 TO 1)

> t

GOTONORM

TXD = 1

t

(LIN = DOMINANT)

> t

LIN(DOM)(DET)

t

(NSLP = 0 AFTER 1 TO 0)

> t

GOTOSLEEP

t

(NSLP = 0 AFTER 1 TO 0)

> t

GOTOSLEEP

t

(NSLP = 1 AFTER 0 TO 1)

> t

GOTONORM

TXD = 0

INITIAL

POWER-ON STATE

STANDBY MODE

t

(NSLP = 1 AFTER 0 TO 1)

> t

GOTONORM

TXD = 1

t

(NSLP = 1 AFTER 0 TO 1)

> t

GOTONORM

TXD = 0

(t

NWAKE

= 0 AFTER 1 TO 0) > t

NWAKE

OR

t

(LIN = 0 AFTER 1 TO 0)

>t

BUS

t

(LIN = RECESSIVE)

> t

LIN(DOM)(REC)

DISABLE MODE

t

(NWAKE = 0 AFTER 1 TO 0)

> t

NWAKE

t

(NSLP = 0 AFTER 1 TO 0)

> t

GOTOSLEEP

t

(NSLP = 1 AFTER 0 TO 1)

> t

GOTONORM

t

(LIN = DOMINANT)

> t

LIN(DOM)(DET)

t

(LIN = RECESSIVE)

> t

LIN(DOM)(REC)

Figure 2. MAX13021 Operating Modes

Low Slope Mode

Low slope mode is identical to normal slope mode, with
the exception of the LIN transmitter. In low slope mode,
the transmitter slew-rate is further limited for improved
EME performance. Maximum data rate is limited to

10.4kbaud due to the increased slew-rate limiting of the
LIN transmitter. From standby or sleep mode, drive
TXD logic-low, then drive NSLP logic-high for longer
than t

GOTONORM

to enter low slope mode. Drive NSLP

logic-low for longer than t

GOTOSLEEP

to force the

device into sleep mode from low slope mode.

LIN Bus Dominant Management

(MAX13021)

The MAX13021 provides two additional states to imple­ment reduced current consumption during a LIN-to­GND short condition. When the MAX13021 detects a
dominant-clamped fault on LIN, the device disables the
transmitter and enters a low-power fail-safe mode. The
receiver is disabled and a low-power comparator is
enabled to monitor the LIN bus. When a recessive state
is detected on LIN, the device exits fault mode and
returns to standby mode.

Fault Mode (MAX13021)

The device enters fault mode from normal slope or low
slope mode when a dominant state is detected on LIN
for longer than t

LIN(DOM)(DET)

. In fault mode, the slave

termination resistor from LIN to BAT is disconnected,
and the LIN transmitter and receiver are disabled to
reduce power consumption. INH output remains pulled
high. A low-power comparator is enabled to monitor the
LIN bus. Fault mode is cleared, and the MAX13021
enters standby mode when a recessive state is detect­ed on LIN for longer than t

LIN(DOM)(REC)

.

Disable Mode (MAX13021)

The MAX13021 enters disable mode from fault mode
after NSLP is driven logic-low for longer than
t

GOTOSLEEP

. The INH output is high impedance in dis­able mode to reduce current consumption. The LIN
transmitter and receiver are disabled, and the slave ter­mination resistor from LIN to BAT is disconnected. A
low-power comparator is enabled to monitor the LIN
bus. The MAX13021 enters fault mode when NSLP is
driven logic-high for longer than t

GOTONORM

. The
device enters sleep mode if a recessive state is detect­ed on LIN for longer than t

LIN(DOM)(REC)

.

Local and Remote Wake-Up Events

The MAX13020/MAX13021 recognize local and remote
wake-up events from sleep mode. The MAX13021 also
recognizes local wake-up events from disable mode. A
local wake-up event is detected when NWAKE is held
at logic-low for longer than t

GOTONORM

after a falling

edge. NWAKE is internally pulled up to BAT with a

MAX13020/MAX13021

±60V Fault-Protected LIN Transceivers

______________________________________________________________________________________ 11

MODE

NSLP

TXD

RXD INH

TRANSMITTER

RECEIVER

COMMENTS

SLEEP 0 330kΩ

Disabled Disabled No wake-up events detected

STANDBY 0

330kΩ or

strong

pulldown

0 1 Disabled Disabled

Wake-up detected from sleep
mode. TXD indicates wake-up
source. (Note 1)

NORMAL
SLOPE

1 330kΩ LIN 1 Normal slope Enabled (Notes 2, 3, 4)

LOW SLOPE

1 330kΩ LIN 1 Low slope Enabled (Notes 2, 3, 5)

FAULT* 1 330kΩ LIN 1 Disabled

—

DISABLE* 0 330kΩ LIN

Disabled

—

Table 1. Operating Modes

Note 1: Standby mode is entered automatically after a local or remote wake-up event from sleep mode. INH and the 30kΩ termina-

tion resistor on LIN are enabled.

Note 2: The internal wake-up source flag on TXD is cleared upon entering normal slope or low slope mode.
Note 3: The internal wake-up interrupt flag on RXD is cleared upon entering normal slope or low slope mode.
Note 4: Drive NSLP high for longer than t

GOTONORM

with TXD logic-high to enter normal slope mode.

Note 5: Drive NSLP high for longer than t

GOTONORM

with TXD logic-low to enter low slope mode.

*MAX13021 only.

High-Z = High impedance.

PULLDOWN

High-Z High-Z

High-Z

Low power

Low power

MAX13020/MAX13021

10µA pullup. In applications where local wake-up capa­bility is not required, connect NWAKE to BAT. For
improved EMI performance, connect NWAKE to BAT
through a 5kΩ resistance.

A remote wake-up event is generated when a reces­sive-dominant-recessive sequence is detected on LIN.
The dominant state must be asserted longer than t

BUS

to generate a remote wake-up (Figure 3).

Wake-Up Source Recognition

When a wake-up event is detected, the MAX13020/
MAX13021 enter standby mode and present the wake-up
interrupt on RXD as a logic-low. The wake-up source flag
is presented on TXD as a strong pulldown in the case of a
local wake-up. In the case of a remote wake-up, TXD is
pulled low by the internal 330kΩ resistor only. To read the
wake-up source flag, pull TXD high with an external
pullup resistor (see Reading the Wake-Up Source Flag
section.) The wake-up interrupt and wake-up source flag
are cleared when the MAX13020/MAX13021 transition to
normal slope mode or low slope mode. The thermal-shut­down circuit forces the driver outputs into high-imped­ance state if the die temperature exceeds +160°C.
Normal operation resumes when the die temperature
cools to +140°C.

Fail-Safe Features

The MAX13020/MAX13021 include a number of fail­safe features to handle fault conditions. Internal pull­downs are provided on control inputs TXD and NSLP to
force the device into a known state in the event that
these inputs are disconnected.

LIN Short-Circuit Protection

The LIN transmitter is current-limited to prevent dam­age from LIN-to-BAT shorts.

TXD Dominant Timeout

If TXD is shorted to GND or is otherwise held low, the
resulting dominant LIN state blocks traffic on the LIN
bus. In normal slope and low slope modes, the LIN
transmitter is disabled if TXD is held at logic-low for
longer than t

TXD(DOM)(DIS)

. The transmitter is re-

enabled on the next rising edge on TXD.

Loss of Power

If BAT or GND are disconnected, interrupting power to
the MAX13020/MAX13021, LIN remains high imped­ance to avoid loading the LIN bus. Additionally, RXD is
high impedance when BAT is disconnected, preventing
current flow from a connected microcontroller.

LIN Bus Dominant Management (MAX13021)

The MAX13021 provides LIN bus dominant manage­ment protection to reduce current consumption during
a LIN-to-GND short condition. When the LIN-to-GND
short is cleared, and a recessive LIN state is detected,
the MAX13021 returns to standby or sleep mode.

ESD Protection

As with all Maxim devices, ESD-protection structures
are incorporated on all pins to protect against ESDs
encountered during handling and assembly. The LIN,
NWAKE, and BAT pins are protected up to ±4kV as
measured by the IEC61000-4-4 Contact Discharge
Model. LIN is protected to ±12kV Human Body Model.
Protection structures prevent damage caused by ESD
events in all operating modes and when the device is
unpowered.

ESD Test Conditions

ESD performance depends on a variety of conditions.
Contact Maxim for a reliability report documenting test
setup, methodology, and results.

Applications Information

Master LIN Nodes

Configure the MAX13020/MAX13021 as a master LIN
node by connecting a 1kΩ resistor from LIN to INH with
a blocking diode (see the Typical Operating Circuit.)
INH is held at a logic-high level in normal slope, low
slope, standby, and fault (MAX13021) modes. INH is
high impedance in sleep mode and disable mode
(MAX13021) to reduce power consumption.

±60V Fault-Protected LIN Transceivers

12 ______________________________________________________________________________________

STANDBY
MODE

V

LIN

LIN RECESSIVE

LIN DOMINANT

t

BUS

0.4 x V

BAT

0.6 x V

BAT

SLEEP MODE

Figure 3. Remote Wake-Up Timing

Reading the Wake-Up Source Flag

When a wake-up event is detected in sleep mode, the
MAX13020/MAX13021 transition to standby mode and
present the wake-up source flag on TXD as a strong
pulldown in the case of a local wake-up. In the case of
a remote wake-up event, TXD is pulled to ground only
by an internal resistor. The wake-up source flag can be
determined by connecting a pullup resistor to TXD.
Choose the external pullup resistor such that TXD is a
logic-high when a remote wake-up occurs, and when a
local wake-up occurs and the strong pulldown drives
TXD low.

MAX13020/MAX13021

±60V Fault-Protected LIN Transceivers

______________________________________________________________________________________ 13

t

BIT

t

BIT

t

BIT

t

BUS(DOM)(MAX)

t

BUS(REC)(MIN)

V

TH(REC)(MAX)

V

TH(DOM)(MAX)

V

TH(REC)(MIN)

V

TH(DOM)(MIN)

t

BUS(DOM)(MIN)

t

BUS(REC)(MAX)

t

P(rx1)F

t

P(rx1)F

t

P(rx2)F

t

P(rx2)F

THRESHOLDS OF
RECEIVING NODE 1

THRESHOLDS OF
RECEIVING NODE 1

V

TXDL

V

SUP

(1)

LIN BUS
SIGNAL

V

RXDL1

V

RXDL2

RECEIVING
NODE 1

RECEIVING
NODE 2

(1) TRANSCEIVER SUPPLY OF TRANSMITTING NODE.

Figure 4. LIN Waveform Definition

BAT

NWAKE

TXD

INH

NSLP

GND

LIN

RXD

0.1µF

R

L

C

L

+5V

MAX13020
MAX13021

Figure 5. Test Circuit for AC Characteristics

MAX13020/MAX13021

±60V Fault-Protected LIN Transceivers

14 ______________________________________________________________________________________

Chip Information

PROCESS: BiCMOS

NSLP

NWAKE

INH

TXD

RXD

BAT

LIN

TXD

TIME-OUT

TIMER

RXD/INT

SLEEP/NORMAL

TIMER

WAKE-UP

TIMER

MODE CONTROL

BUS TIMER

SLEW

RATE

CONTROL

THERMAL

SHUTDOWN

FILTER

30kΩ

GND

VBAT/2

MAX13020
MAX13021

5µA

Functional Diagram

LIN

GNDTXD

1

2

87INH

BATNSLP

NWAKE

RXD

SO

TOP VIEW

3

4

6

5

MAX13020
MAX13021

+

Pin Configuration

MAX13020/MAX13021

±60V Fault-Protected LIN Transceivers

Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.

Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 15

© 2006 Maxim Integrated Products is a registered trademark of Maxim Integrated Products, Inc.

Boblet

Package Information

(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information,
go to www.maxim-ic.com/packages

.)

SOICN .EPS

PACKAGE OUTLINE, .150" SOIC

1

1

21-0041

B

REV.DOCUMENT CONTROL NO.APPROVAL

PROPRIETARY INFORMATION

TITLE:

TOP VIEW

FRONT VIEW

MAX

0.010

0.069

0.019

0.157

0.010

INCHES

0.150

0.007

E

C

DIM

0.014

0.004

B

A1

MIN

0.053A

0.19

3.80 4.00

0.25

MILLIMETERS

0.10

0.35

1.35

MIN

0.49

0.25

MAX

1.75

0.050

0.016L

0.40 1.27

0.3940.386D

D

MINDIM

D

INCHES

MAX

9.80 10.00

MILLIMETERS

MIN

MAX

16

AC

0.337 0.344 AB8.758.55 14

0.189 0.197 AA5.004.80 8

N MS012

N

SIDE VIEW

H 0.2440.228 5.80 6.20

e 0.050 BSC 1.27 BSC

C

HE

e

B

A1

A

D

0-8

L

1

VARIATIONS: