PART TOP VIEW TXD V CC. Maxim Integrated Products 1

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1 9-2939; Rev ; 9/3 5V, Mbps, Low Supply Current General Description The interface between the controller area network (CAN) protocol controller and the physical wires of the bus lines in a CAN. They are primarily intended for printer and telecom backplane applications requiring data rates up to Mbps. These devices provide differential transmit capability to the bus and differential receive capability to the CAN controller. The MAX358 output common-mode range is from -7V to +2V. The MAX359 output common-mode range is from V to. The MAX359 contains an internal switch termination resistor that makes it ideal for JetLink applications. The MAX358 features four different modes of operation: high speed, slope control, standby, and shutdown. The MAX359 features three different modes of operation: high speed, slope control, and shutdown. Highspeed mode allows data rates up to Mbps. In slope-control mode, the slew rate may be optimized for data rates up to 5kbps, so the effects of EMI are reduced, and unshielded twisted or parallel cable can be used. In standby mode, the transmitters are shut off and the receivers are put into low-current mode. In shutdown mode, the transmitter and receiver are switched off. The are available in an 8-pin SO package and are specified over the -4 C to +25 C temperature range. Printers JetLink Industrial Control Networks Telecom Backplane Consumer Applications Applications Features Four Operating Modes High-Speed Operation Up to Mbps Slope-Control Mode to Reduce EMI (4kbps to 5kbps) Low-Current Shutdown Mode Standby Mode (MAX358 Only) Thermal Shutdown Current Limiting ESD Protection ±2kV Human Body Model Ordering Information PART TEMP RANGE PIN-PACKAGE MAX358ASA -4 C to +25 C 8 SO MAX359ASA -4 C to +25 C 8 SO TOP VIEW Selector Guide PART TERMINATION RESISTOR STANDBY MAX358ASA No Yes MAX359ASA Yes No Pin Configurations 8 RS 8 RS GND 2 3 MAX CANH GND 2 3 MAX CANH 4 5 SHDN 4 5 TERM SO SO Typical Operating Circuit appears at end of data sheet. Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at , or visit Maxim s website at

2 ABSOLUTE MAXIMUM RATINGS to GND...-.3V to +6V, RS, SHDN, TERM to GND...-.3V to +6V to GND...-.3V to +6V CANH, to GND (MAX358) V to +2.5V CANH, to GND (MAX359)...-.3V to ( +.3V) 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. DC ELECTRICAL CHARACTERISTICS Continuous Power Dissipation (T A = +7 C) 8-Pin SO (derate 5.9mW/ C above +7 C)...47mW Operating Temperature Range...-4 C to +25 C Maximum Junction Temperature...+5 C Storage Temperature Range C to +5 C Lead Temperature (soldering, s)...+3 C ( = +5V ±%, T A = T MIN to T MAX, R L = 6Ω, C L = pf. Typical values are at = +5V and T A = +25 C.) (Note ) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Dominant 4 7 Supply Current I S Recessive 2 5 ma Quiescent Current Standby Mode I Q Standby, MAX µa V SHDN =, MAX358 5 Shutdown Current I SHDN V TERM = V RS =, MAX359 V TERM = V, V RS =, MAX359 5 µa Thermal-Shutdown Threshold V TSH 6 C Thermal-Shutdown Hysteresis 25 C INPUT LEVELS High-Level Input Voltage V IH 2 V Low-Level Input Voltage V IL.8 V Input Capacitance C IN (Note 3) 5 2 pf Pullup Resistor R IN 5 kω TERM INPUT LEVELS (MAX359) High-Level Input Voltage V TRH 2 V Low-Level Input Voltage V TRL.8 V TERM Pullup Resistor R PU 5 kω CANH, TRANSMITTER Recessive Bus Voltage V CANH, V V =, no load 2 3 V V =, no load, V RS = (standby mode), MAX358 CANH Output Voltage V CANH V = V mv Output Voltage V V = V V Differential Output (V CANH - V ) V = V, = 5V ±5% V V CANH, V = V, = 5V ±% V V V = V, R L = 45Ω.2 3 V =, no load mv V 2

3 DC ELECTRICAL CHARACTERISTICS (continued) ( = +5V ±%, T A = T MIN to T MAX, R L = 6Ω, C L = pf. Typical values are at = +5V and T A = +25 C.) (Note ) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS -7V V CANH V, MAX CANH Short-Circuit Current I CANHSC V CANH = V, MAX V 2V, MAX Short-Circuit Current I SC V =, MAX Termination Resistor R TERM V TERM =, MAX Ω OUTPUT LEVELS High-Output Voltage Level V OH I = -µa.8 x V Low-Output Voltage Level V OL I =.6mA.4 V DC BUS RECEIVER (Note 2) Differential Input Voltage (Recessive) MAX V DIFF MAX358, V RS = (standby mode) MAX ma ma V Differential Input Voltage (Dominant) MAX V DIFF MAX358, V RS = (standby mode). 7 MAX359.9 V Differential Input Hysteresis V DIFF(HYST) mv CANH and Input Resistance R I 5 25 kω Differential Input Resistance R DIFF kω MODE SELECTION (RS) Input Voltage for High Speed V SLP.3 x Input Voltage for Standby V STBY V SHDN MAX358 MAX359 Slope-Control Mode Voltage V SLOPE R RS = 25kΩ to 2kΩ Slope-Control Mode Current I SLOPE R RS = 25kΩ to 2kΩ - -2 µa High-Speed Mode Current I HS V RS = V -5 µa SHUTDOWN (MAX358) SHDN Input Voltage High V SHDNH 2 V SHDN Input Voltage Low V SHDNL.8 V SHDN Pulldown Resistor R INDHDN 5 kω.75 x.4 x.6 x V V V 3

4 TIMING CHARACTERISTICS ( = +5V ±%, R L = 6Ω, C L = pf, T A = T MIN to T MAX. Typical values are at = +5V and T A = +25 C.) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Delay to Bus Active, Figure Delay to Bus Inactive, Figure Delay Bus to Receiver Active, Figure Delay Bus to Receiver Inactive, Figure Differential Output Slew Rate t ON t OFF t ON t OFF SR V RS = V ( Mbps) 5 R RS = 25kΩ ( 5kbps) 25 R RS = kω ( 25kbps) 45 R RS = 2kΩ ( 62.5kbps) 7 V RS = V ( Mbps) 7 R RS = 25kΩ ( 5kbps) 8 R RS = kω ( 25kbps) 5 R RS = 2kΩ ( 62.5kbps) V RS = V ( Mbps) 8 R RS = 25kΩ ( 5kbps) 5 R RS = kω ( 25kbps) 5 R RS = 2kΩ ( 62.5kbps) 8 V RS = V ( Mbps) R RS = 25kΩ ( 5kbps) 2 R RS = kω ( 25kbps) 5 R RS = 2kΩ ( 62.5kbps) V RS = V ( Mbps) R RS = 25kΩ ( 5kbps) 7 R RS = kω ( 25kbps).6 R RS = 2kΩ ( 62.5kbps).8 Bus Dominant to Active t DL V RS >.8 x (standby), MAX358, Figure 2 Note : All currents into device are positive; all currents out of the device are negative. All voltages are referenced to device ground, unless otherwise noted. Note 2: (V = ; CANH and externally driven; -7V < V CANH, V < 2V for MAX358; V < V CANH, V < for MAX359, unless otherwise specified). Note 3: Specification guaranteed by design, not production tested. Note 4: No other devices on the BUS. Note 5: BUS externally driven. ns ns ns ns V/µs µs Standby to Receiver Active t SBL BUS dominant, MAX358, Figure 2 4 µs SHDN to Bus Inactive t OFFSHDN = GND, MAX358, Figure 3 (Note 4) µs SHDN to Receiver Active t ONSHDN BU S d om i nant, M AX 358, Fi g ur e 3 ( N ote 5) 4 µs RS to Bus Inactive t OFFSHDN = GND, MAX359, Figure 3 (Note 4) µs RS to Receiver Active t ONSHDN BUS dominant, MAX359, Fi g ur e 3 ( N ote 5) 4 µs TERM to Resistor Switched On t ONRT V RS = (part in shutdown), MAX359, Figure 4 TERM to Resistor Switched Off t OFFRT V RS = (part in shutdown), MAX359, Figure 4 4 ns 4 ns ESD Protection Human Body Model 2 ±kv 4

5 /2 /2 t ON t OFF V DIFF.9V.5V t ON t OFF /2 /2 RS V DIFF x.75 t SBL Timing Diagrams BUS EXTERNALLY DRIVEN /2 /2.V t DL Figure. Timing Diagram Figure 2. Timing Diagram for Standby Signal (MAX358) SHDN /2 /2 CANH C L 5Ω t OFFSHDN t ONSHDN 5Ω V DIFF.5V BUS EXTERNALLY DRIVEN TERM /2 /2 /2 t ONRT t OFFRT CANH - V - V Figure 3. Timing Diagram for Shutdown Signal Figure 4. Test Circuit and Diagram for TERM Timing (MAX359) 5

6 Typical Operating Characteristics ( = +5V, R L = 6Ω, C L = pf, T A = +25 C, unless otherwise specified.) SLEW RATE (V/µs) SUPPLY CURRENT (µa) SLEW RATE vs. R RS AT kbps R RS (kω) MAX359 SUPPLY CURRENT vs. TEMPERATURE IN SHUTDOWN MODE (TERM = ) TEMPERATURE ( C) SUPPLY CURRENT (µa) MAX358/59 toc MAX358/59 toc4 SUPPLY CURRENT (ma) RECEIVER PROPAGATION DELAY (ns) MAX358 SUPPLY CURRENT vs. TEMPERATURE IN SHUTDOWN SHDN = RS = GND = SUPPLY CURRENT vs. DATA RATE T A = -4 C T A = +25 C T A = +25 C DATA RATE (kbps) RECEIVER PROPAGATION DELAY vs. TEMPERATURE 9 8 RECESSIVE DOMINANT 3 2 R RS = GND TEMPERATURE ( C) MAX358/59 toc7 VOLTAGE (V) MAX358/59 toc2 MAX358/59 toc5 SUPPLY CURRENT (µa) DRIVER PROPAGATION DELAY (ns) MAX359 SUPPLY CURRENT vs. TEMPERATURE IN SHUTDOWN MODE (TERM = GND) TEMPERATURE ( C) DRIVER PROPAGATION DELAY vs. TEMPERATURE DOMINANT RECESSIVE R RS = GND TEMPERATURE ( C) RECEIVER OUTPUT LOW vs. OUTPUT CURRENT T A = +25 C T A = +25 C T A = -4 C MAX358/59 toc8 MAX358/59 toc3 MAX358/59 toc TEMPERATURE ( C) OUTPUT CURRENT (ma) 6

7 Typical Operating Characteristics (continued) ( = +5V, R L = 6Ω, C L = pf, T A = +25 C, unless otherwise specified.) RECEIVER OUTPUT HIGH (VCC - ) (V) RECEIVER OUTPUT HIGH vs. OUTPUT CURRENT T A = +25 C T A = +25 C T.5 A = -4 C OUTPUT CURRENT (ma) MAX358/59 toc9 DIFFERENTIAL VOLTAGE (V) DIFFERENTIAL VOLTAGE vs. DIFFERENTIAL LOAD RL T A = +25 C T A = -4 C T A = +25 C DIFFERENTIAL LOAD RL (Ω) MAX358/59 toc RECEIVER PROPAGATION DELAY MAX358/59 toc CANH - DRIVER PROPAGATION DELAY MAX358/59 toc2 5V/div R RS = 24kΩ 2V/div R RS = kω R RS = 8kΩ 2ns/div µs/div DRIVER PROPAGATION DELAY (RS = GND) 2ns/div MAX358/59 toc3 5V/div CANH - LOOPBACK PROPAGATION DELAY (ns) LOOPBACK PROPAGATION DELAY vs. R RS R RS (kω) MAX358/59 toc4 7

8 MAX358 PIN MAX359 NAME 2 2 GND Ground FUNCTION Pin Description Transmit Data Input. is a CMOS/TTL-compatible input from a CAN controller. has an internal 75kΩ pullup resistor. 3 3 Supply Voltage. Bypass to GND with a.µf capacitor. 4 4 Receive Data Output. is a CMOS/TTL-compatible output. 5 SHDN 6 6 CAN Bus Line Low 7 7 CANH CAN Bus Line High 8 8 RS Shutdown Input, CMOS/TTL-Compatible Input. Drive SHDN high to put the IC into shutdown mode. SHDN has an internal 75kΩ pulldown resistor to GND. Mode Select Input. Drive RS low or connect to GND for high-speed operation. Connect a resistor between RS and GND to control output slope. For the MAX358, drive RS high to put into standby mode. (see Mode Selection section). For the MAX359, drive RS above.75 x to select shutdown mode. 5 TERM Terminate Input, CMOS/TTL Compatible. Drive TERM high or leave floating to terminate the device with a 2Ω across the CANH and. Drive TERM low to disconnect this resistor. TERM has an internal 75kΩ pullup resistor to. Functional Diagram THERMAL SHUTDOWN MAX358/ MAX359 CANH R b R T TRANSMITTER CONTROL /2 + R b - RS MODE SELECTION TERM (MAX359) RECEIVER SHUTDOWN GND SHDN (MAX358).75V 8

9 Detailed Description The interface between the protocol controller and the physical wires of the bus lines in a CAN. They are primarily intended for printer and telecom backplane applications requiring data rates up to Mbps. These devices provide differential transmit capability to the bus and differential receive capability to the CAN controller. The MAX358 output common-mode range is from -7V to +2V. The MAX359 output common-mode range is from V to. The MAX359 contains an internal switch termination resistor that makes it ideal for JetLink applications. The MAX358 features four different modes of operation: high-speed, slope control, standby, and shutdown. The MAX359 features three different modes of operation: high speed, slope control, and shutdown. High-speed mode allows data rates up to Mbps. In slope-control mode, the slew rate may be optimized for data rates up to 5kbps, so the effects of EMI are reduced, and unshielded twisted or parallel cable can be used. In standby mode, the transmitters are shut off and the receivers are put into low-current mode. In shutdown mode, the transmitter and receiver are switched off. The transceivers operate from a single +5V supply and draw 4mA of supply current in dominant state and 2mA in recessive state. In standby mode, supply current is reduced to 5µA. In shutdown mode, supply current is µa for the MAX358 and 5µA for the MAX359. CANH and are output short-circuit current limited and are protected against excessive power dissipation by thermal-shutdown circuitry that places the driver outputs into a high-impedance state. Transmitter The transmitter converts a single-ended input () from the CAN controller to differential outputs for the bus lines (CANH, ). The truth table for the transmitter and receiver is given in Tables and 2. Table. Transmitter and Receiver Truth Table for MAX358 When Not Connected to the Bus RS SHDN CANH BUS STATE Low V RS <.75 x Low High Low Dominant Low High or float V RS <.75 x Low X V RS >.75 x Low 5kΩ to 25kΩ to /2 5kΩ to 25kΩ to GND 5kΩ to 25kΩ to /2 5kΩ to 25kΩ to GND Recessive Recessive X X High Floating Floating Floating High High High Table 2. Transmitter and Receiver Truth Table for MAX359 When Not Connected to the Bus RS TERM CANH BUS STATE Low V RS <.75 x Low High Low Dominant Low Low V RS <.75 x High High or float V RS <.75 x Low High or float V RS <.75 x High High 9 Low 2Ω terminating resistor across 5kΩ to 25kΩ to /2 5kΩ to 25kΩ to /2 5kΩ to 25kΩ to /2 5kΩ to 25kΩ to /2 2Ω terminating resistor across Dominant Recessive Recessive X V RS >.75 x Low Floating Floating Floating High X V RS >.75 x High Floating Floating 2Ω terminating resistor across Floating Low High High High

10 Receiver The receiver reads differential input from the bus lines (CANH, ) and transfers this data as a singleended output () to the CAN controller. It consists of a comparator that senses the difference V = (CANH - ) with respect to an internal threshold of.7v. If this difference is positive (i.e., V >.7), a logic low is present at. If negative (i.e., V <.7V), a logic high is present. The receiver always echoes the CAN BUS data. The CANH and common-mode range is -7V to +2V for the MAX358, and V to for the MAX359. is logic high when CANH and are either shorted, or terminated and undriven. Mode Selection High-Speed Mode Connect RS to ground to set the to high-speed mode. When operating in high-speed mode, the can achieve transmission rates of up to Mbps. In high-speed mode, use shielded twisted-pair cable to avoid EMI problems. Slope-Control Mode Connect a resistor from RS to ground to select slopecontrol mode (Table 3). In slope-control mode, CANH and slew rates are controlled by the resistor connected to the RS pin. Maximum transmission speeds are controlled by R RS, and range from 4kbps to 5kbps. Controlling the rise and fall slopes reduces EMI and allows the use of an unshielded twisted pair or a parallel pair of wires as bus lines. The transfer function for selecting the resistor value is given by: R RS (kω) 2,5/(maximum speed in kbps) See the Slew Rate vs. R RS graph in the Typical Operating Characteristics. Standby Mode If a logic-high level is applied to RS, the MAX358 enters a low-current standby mode. In this mode, the transmitter is switched off and the receiver is switched to a low-current/low-speed state. If dominant bits are detected, switches to low level. The microcontroller should react to this condition by switching the transceiver back to normal operation. When the MAX358 enters standby mode, goes high for 4µs (max) regardless of the BUS state. However, after 4µs, goes low only when the BUS is dominant; otherwise, remains high (when the BUS is recessive). For proper measurement of standby to receiver active time (t SBL ), the BUS should be in a dominant state (see Figure 2). Shutdown Mode Drive SHDN high to enter shutdown mode on the MAX358. Connect SHDN to ground or leave it floating for normal operation. On the MAX359, drive RS high to enter shutdown. TERM Drive TERM high (to ) or leave it floating to terminate the MAX359 with 2Ω resistor connected across the CANH and. Connect TERM to ground to disconnect this resistor. Thermal Shutdown If the junction temperature exceeds +6 C, the device is switched off. The hysteresis is approximately 25 C, disabling thermal shutdown once the temperature drops to +35 C. In thermal shutdown, CANH and go recessive and all IC functions are disabled. Table 3. Mode Selection Truth Table CONDITION FORCED AT PIN RS MODE RESULTING CURRENT AT RS (µa) V RS <.3 x High speed I RS < 5.4 x <V RS <.6 x Slope control µa < I RS < 2 V RS >.75 x Standby (MAX358) I RS < V RS >.75 x Shutdown (MAX359) I RS <

11 Applications Information Reduced EMI and Reflections In slope-control mode, the CANH and outputs are slew-rate limited, minimizing EMI and reducing reflections caused by improperly terminated cables. In multidrop CAN applications, it is important to maintain a direct point-to-point wiring scheme. A single pair of wires should connect each element of the CAN bus, and the two ends of the bus should be terminated with 2Ω resistors. A star configuration should never be used. Any deviation from the point-to-point wiring scheme creates a stub. The high-speed edge of the CAN data on a stub can create reflections back down the bus. These reflections can cause data errors by eroding the noise margin of the system. Although stubs are unavoidable in a multidrop system, care should be taken to keep these stubs as small as possible, especially in high-speed mode. In slope-control mode, the requirements are not as rigorous, but stub length should still be minimized. Power Supply and Bypassing The require no special layout considerations beyond common practices. Bypass to GND with a.µf ceramic capacitor mounted close to the IC with short lead lengths and wide trace widths. Chip Information TRANSISTOR COUNT: 24 PROCESS: BiCMOS Typical Operating Circuit 2Ω.µF CAN CONTROLLER CANH MAX358 TX RX SHDN GND 25kΩ 2kΩ RS GND 2Ω

12 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 N TOP VIEW E H INCHES MILLIMETERS DIM A A MIN.53.4 MAX.69. MIN.35. MAX B C e.5 BSC.27 BSC E H L VARIATIONS: DIM D D D INCHES MILLIMETERS MIN MAX MIN MAX N MS AA AB AC SOICN.EPS D A C e B A FRONT VIEW L SIDE VIEW -8 PROPRIETARY INFORMATION TITLE: PACKAGE OUTLINE,.5" SOIC APPROVAL DOCUMENT CONTROL NO. REV. 2-4 B 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. 2 Maxim Integrated Products, 2 San Gabriel Drive, Sunnyvale, CA Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.

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