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LTC2875

Rev A

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TYPICAL APPLICATION

FEATURES DESCRIPTION

±60V Fault Protected

3.3V or 5V 25kV ESD

High Speed CAN FD Transceiver

The LT C

2875 is a robust high speed, low power CAN

transceiver operating on 3.3V or 5V supplies that features

±60V overvoltage fault protection on the data transmis-

sion lines during all modes of operation, including power-

down. The maximum data rate has been extended to

4Mbps to support high speed protocols based on the CAN

physical layer. Supports up to 4Mbps CAN with Flexible

Data Rate (CAN FD). Enhanced ESD protection allows

these parts to withstand ±25kV HBM on the transceiver

interface pins without latchup or damage.

Extended ±36V input common mode range and high

common mode rejection on the CAN receiver provides

tolerance of large ground loop voltages. A sophisticated

CAN driver with active symmetry control maintains tight

control of the common mode voltage for excellent elec

tromagnetic emission, while the variable slew rate and

split termination support allow additional EME reduction.

CAN Bus Link with Large Ground Loop Voltage

LTC2875 Transmitting at 4Mbps

from a 3.3V Supply

APPLICATIONS

Protected from Overvoltage Line Faults to ±60V

3.3V or 5V Supply Voltage

High Speed CAN FD Operation Up to 4Mbps

±25kV ESD Interface Pins, ±8kV All Other Pins

Variable Slew Rate Driver with Active Symmetry

Control and SPLIT Pin for Low Electromagnetic

Emission (EME)

Extended Common Mode Range (±36V)

Ideal Passive Behavior to CAN Bus with Supply Off

Current Limited Drivers and Thermal Shutdown

Power-Up/Down Glitch-Free Driver Outputs

Micropower Shutdown Mode

Transmit Data (TXD) Dominant Timeout Function

ISO 11898-2 and CAN FD Compliant

DeviceNet Compatible

Up to MP-Grade Available (–55°C to 125°C)

3mm × 3mm 8-Lead DFN and SO-8 Packages

Industrial Control and Instrumentation Networks

Automotive and Transportation Electronics

Building Automation, Security Systems, HVAC

Medical Equipment

2875 TA01a

120Ω

LTC2875

CANH

CANL

GND1

AC GROUND

LOOP ≤ 36V

PEAK

GND2

CANL

CC1

CC2

CANH

LTC2875

RXD1

TXD1

RS1

RXD2

TXD2

RS2

120Ω

100ns/DIV

TXD

2V/DIV

RXD

2V/DIV

CANH

1V/DIV

CANL

1V/DIV

2875 TA01b

COMMON MODE

Downloaded from Arrow.com.

Summary of content (22 pages)

PAGE 1
LTC2875 ±60V Fault Protected 3.3V or 5V 25kV ESD High Speed CAN FD Transceiver DESCRIPTION FEATURES n n n n n n n n n n n n n n n Protected from Overvoltage Line Faults to ±60V 3.
PAGE 2
LTC2875 ABSOLUTE MAXIMUM RATINGS (Note 1) Supply Voltages VCC........................................................... –0.3V to 6V Logic Input Voltages (TXD, RS) ................... –0.3V to 6V Interface I/O: CANH, CANL, SPLIT .............. –60V to 60V Receiver Output (RXD) ..................–0.3V to (VCC + 0.3V) Bus Differential Voltage (CANH-CANL)....... –120V to 120V Operating Ambient Temperature Range (Note 4) LTC2875I..............................................–40°C to 85°C LTC2875H.............
PAGE 3
LTC2875 ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VCC = 3.3V or 5V, Figure 1 applies with RL = 60Ω, RS = 0V, TYP values at VCC = 5V unless otherwise noted. (Note 2) SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Supplies VCC Supply Voltage 3.3V VCC Range l 3 3.3 3.6 V 5V VCC Range l 4.5 5 5.5 V ICC(R) Supply Current (Recessive) l 1 1.
PAGE 4
LTC2875 ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VCC = 3.3V or 5V, Figure 1 applies with RL = 60Ω, RS = 0V, TYP values at VCC = 5V unless otherwise noted. (Note 2) SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Common Mode Stabilization Output SPLIT VO_SPLIT IOS_SPLIT SPLIT Output Voltage SPLIT Short-Circuit Current –500μA ≤ I(SPLIT) ≤ VCC = 5V 500μA VCC = 3.3V l 1.5 2.5 3.
PAGE 5
LTC2875 SWITCHING CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VCC = 3.3V or 5V, Figure 1 applies with RL = 60Ω, CL = 100pF, RSL = 0Ω, RS = 0V, TYP values at VCC = 5V unless otherwise noted.
PAGE 6
LTC2875 TEST CIRCUITS RSL RS CANH LTC2875 TXD RS GND CANH VCC VCC CANL RXD RXD SPLIT TXD 47µF 15pF RL/2 1% VOD CM RL/2 1% 0.1µF CANL VOC GND RSL = 0Ω EXCEPT AS NOTED 2875 TC01 Figure 1. All Electrical Characteristic Measurements RSL RS CANH LTC2875 TXD RS GND CANH VCC VCC CANL RXD RXD SPLIT TXD 15pF 47µF RL/2 1% CL 100pF VOD RL/2 1% 4.7nF 0.1µF CANL GND RSL = 0Ω EXCEPT AS NOTED 2875 TC02 Figure 2.
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LTC2875 TEST CIRCUITS RS HIGH TXD 1/2 VCC LTC2875 LOW VCC CANH 1k CANL DOMINANT RXD VOD 47µF 15pF 0.9V TXD RS GND CANH VCC CANL RXD SPLIT 0.1µF + V 1.5V – GND 0.5V RECESSIVE tTOTXD 2875 TC04 Figure 4. TXD Dominant Timeout Time HIGH RS 0.6VCC 0.9VCC RXD LOW HIGH 1/2 VCC 1/2 VCC tENRX tSHDNRX LOW 2875 TC05 Figure 5. RXD Enable and Disable Timing HIGH RS 0.6VCC TXD 0.9VCC LOW HIGH 1/2 VCC LOW CANH CANL DOMINANT 0.9V VOD 0.
PAGE 8
LTC2875 TYPICAL PERFORMANCE CHARACTERISTICS TA = 25°C, VCC = 3.3V or 5V, RL = 60Ω, CL = 100pF, RSL = 0Ω, RS = 0V unless otherwise noted. 3.0 55 2.6 50 50 2.4 ICC(R) (mA) ICC(D) (mA) 60 2.8 55 45 40 2.2 2.0 1.8 1.6 35 3.5 4 4.5 VCC (V) 1.0 5.5 5 3 3.5 2875 G01 Supply Current (Recessive) vs Temperature 4 4.5 VCC (V) 2875 G03 Driver Differential Output Voltage (Dominant) vs Temperature 23 2.9 22 2.6 2.7 VCC = 5V 2.0 VCC = 5V 1.8 VCC = 3.3V 1.6 2.5 21 VOD(D) (V) 2.
PAGE 9
LTC2875 TYPICAL PERFORMANCE CHARACTERISTICS TA = 25°C, VCC = 3.3V or 5V, RL = 60Ω, CL = 100pF, RSL = 0Ω, RS = 0V unless otherwise noted. Receiver Output Voltage vs Output Current Bus Dominant to RXD Propagation Delay vs Temperature 52 4 RECESSIVE, VCC = 3.3V 3 2 1 0 DOMINANT, VCC = 3.
PAGE 10
LTC2875 PIN FUNCTIONS TXD (Pin 1): Transmit Data Input. Low in dominant state. Integrated 500k pull-up to VCC. CANL (Pin 6): Low Level CAN Bus Line. ±60V tolerant, 25kV ESD. GND (Pin 2): Ground. CANH (Pin 7): High Level CAN Bus Line. ±60V tolerant, 25kV ESD. VCC (Pin 3): Positive Supply. 3V ≤ VCC ≤ 3.6V or 4.5V ≤ VCC ≤ 5.5V. Bypass with 0.1µF ceramic capacitor or larger. RXD (Pin 4): Receiver Data Output. Low in dominant state. Integrated 500k pull-up to VCC.
PAGE 11
LTC2875 BLOCK DIAGRAM 3 VCC 1 TXD 500k VCC 8 RS 250k TXD TIMEOUT SLEW CONTROL PREDRIVE SLEW SHUTDOWN/ SHUTDOWN SLEW VCC 4 RXD 500k RX VCC 5 SPLIT* VCC VCC 40k CANH* 40k CANL* 7 6 1.4k + + – – 1.4k GND 2 2875 BD *±60V TOLERANT, ±25kV HBM PROTECTED PINS Figure 8. LTC2875 Simplified Block Diagram Rev A For more information www.analog.com Downloaded from Arrow.com.
PAGE 12
LTC2875 APPLICATIONS INFORMATION Supply Voltage Ranges The LTC2875 can operate from 3.3V or 5V supplies. An internal comparator monitors the supply voltage and switches internal reference voltages and output drive strengths at approximately 4.1V. Because of the discontinuity in the internal voltages at this switch point, operation with a supply voltage between 3.6V and 4.5V is not recommended.
PAGE 13
LTC2875 APPLICATIONS INFORMATION ±25kV ESD Protection The LTC2875 features exceptionally robust ESD protection. The transceiver interface pins (CANH, CANL, SPLIT) feature protection with respect to GND to ±25kV HBM without latchup or damage, during all modes of operation or while unpowered. All other pins are protected to ±8kV HBM to make the LTC2875 reliable under severe environmental conditions. 4Mbps Operation The LTC2865 features a high speed receiver and transmitter capable of operating up to 4 Mbps.
PAGE 14
LTC2875 APPLICATIONS INFORMATION When operating from a 5V supply the LTC2875 adheres to the ISO 11898-2 CAN bus standard by maintaining drive levels that are symmetric around VCC/2 = 2.5V. An internal common mode reference of VCC/2 is buffered to supply the termination of the receiver input resistors. A second buffer with a high voltage tolerant output supplies VCC/2 to the SPLIT output. When operating from a 3.3V supply the 2.
PAGE 15
LTC2875 APPLICATIONS INFORMATION the voltage on RS increases the slew control current ISC being drawn from the slew control circuit until the voltage reaches ~ 0.9V, where the current drawn from the circuit is ~ –100µA. Below an applied voltage of ~ 0.9V, the slew control circuit sources no additional current, and the current drawn from it remains at ~ –100µA down to 0V. The total current IRS drawn from the RS pin for input voltage 0.9V ≤ VRS ≤ 1.
PAGE 16
LTC2875 APPLICATIONS INFORMATION SPLIT Pin Output for Split Termination Support Split termination is an optional termination technique to reduce common mode voltage perturbations that can produce EME. A split terminator divides the single lineend termination resistor (nominally 120Ω) into two series resistors of half the value of the single termination resistor (Figure 2). The center point of the two resistors is connected to a low impedance voltage source that sets the recessive common mode voltage.
PAGE 17
LTC2875 APPLICATIONS INFORMATION 61000-4-4, and 61000-4-5, which address ESD, EFT, and surge, respectively. The transients produced by the EFT and particularly the surge tests contain much more energy than ESD transients. The LTC2875 is designed for high robustness against ESD, but the on-chip protection is not able to absorb the energy associated with the 61000-4-5 surge transients.
PAGE 18
LTC2875 APPLICATIONS INFORMATION DeviceNet Compatibility DeviceNet is a network standard based on the CAN bus. The DeviceNet standard places requirements on the transceiver that exceed those of the ISO 11898-2 standard. The LTC2875 meets the following DeviceNet requirements: PARAMETER Number of Nodes DeviceNet ISO 11898-2 REQUIREMENT REQUIREMENT LTC2875 64 N/A 166 20kΩ 10kΩ 50kΩ Differential Input Capacitance 25pF (Max) 10pF (Nom) 8.
PAGE 19
LTC2875 PACKAGE DESCRIPTION DD Package 8-Lead Plastic DFN (3mm × 3mm) (Reference LTC DWG # 05-08-1698 Rev C) 0.70 ±0.05 3.5 ±0.05 1.65 ±0.05 2.10 ±0.05 (2 SIDES) PACKAGE OUTLINE 0.25 ±0.05 0.50 BSC 2.38 ±0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED PIN 1 TOP MARK (NOTE 6) 0.200 REF 3.00 ±0.10 (4 SIDES) R = 0.125 TYP 5 0.40 ±0.10 8 1.65 ±0.10 (2 SIDES) 0.75 ±0.05 4 0.25 ±0.05 1 (DD8) DFN 0509 REV C 0.50 BSC 2.38 ±0.10 0.00 – 0.
PAGE 20
LTC2875 PACKAGE DESCRIPTION S8 Package 8-Lead Plastic Small Outline (Narrow .150 Inch) (Reference LTC DWG # 05-08-1610 Rev G) .050 BSC .189 – .197 (4.801 – 5.004) NOTE 3 .045 ±.005 8 .245 MIN .160 ±.005 .010 – .020 × 45° (0.254 – 0.508) NOTE: 1. DIMENSIONS IN 5 .150 – .157 (3.810 – 3.988) NOTE 3 1 RECOMMENDED SOLDER PAD LAYOUT .053 – .069 (1.346 – 1.752) 0°– 8° TYP .016 – .050 (0.406 – 1.270) 6 .228 – .244 (5.791 – 6.197) .030 ±.005 TYP .008 – .010 (0.203 – 0.254) 7 .014 – .019 (0.
PAGE 21
LTC2875 REVISION HISTORY REV DATE DESCRIPTION A 04/19 Added CAN FD claims to title, features, and description PAGE NUMBER 1 Added tBIT specifications to Switching Characteristics table 5 Inserted new Figure 7: Loop Delay Symmetry 7 Corrected lowest data rate in “Transmit Dominant Timeout Function” 13 Rev A Information furnished by Analog Devices is believed to be accurate and reliable.
PAGE 22
LTC2875 TYPICAL APPLICATION Network for IEC Level 4 Protection Against Surge, EFT and ESD MOV LTC2875 VCC CANH_EXTERNAL GDT TBU TVS CANH R GND GDT TBU TVS CANL_EXTERNAL CANL RXD TXD T RS GND MOV 2875 TA02 GDT: BOURNS 2031-15T-SM; 150V GAS DISCHARGE TUBE TBU: BOURNS TBU-CA050-300-WH; 500V TRANSIENT BLOCKING UNIT MOV: BOURNS MOV-7D201K; 200V 13J METAL OXIDE VARISTOR TVS: BOURNS CDSOD323-T36SC; 36V BIDIRECTIONAL TVS DIODE RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LT 1796 Overvoltage