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Details, datasheet, quote on part number:82C250
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Datasheet text preview:
Philips Semiconductors
Objective specification
CAN controller interface
FEATURES · Fully compatible with the "ISO/DIS 11898" standard · High speed (up to 1 Mbaud) · Bus lines protected against transients in an automotive environment · Slope control to reduce radio frequency interference (RFI) · Differential receiver with wide common-mode range for high immunity against electromagnetic interference (EMI) · Thermally protected · Short-circuit proof to battery and ground · Low current standby mode · An unpowered node does not disturb the bus lines · At least 110 nodes can be connected. QUICK REFERENCE DATA SYMBOL VCC ICC 1/tbit VCAN V tpd Tamb PARAMETER supply voltage supply current maximum transmission speed CANH, CANL input/output voltage differential bus voltage propagation delay operating ambient temperature high-speed mode non-return-to-zero CONDITIONS 4.5 - 1 -8 1.5 - -40 MIN. 5.5 170 - +18 3.0 50 +125 GENERAL DESCRIPTION APPLICATIONS
PCA82C250
· High-speed applications (up to 1 Mbaud) in cars.
The PCA82C250 is the interface between the CAN protocol controller and the physical bus. The device provides differential transmit capability to the bus and differential receive capability to the CAN controller.
MAX. V µA
UNIT
Mbaud V V ns °C
ORDERING INFORMATION PACKAGE TYPE NUMBER PINS PCA82C250 PCA82C250T 8 8 PIN POSITION DIP8 SO8 MATERIAL plastic plastic CODE SOT97-1 SOT96-1
September 1994
7-69
Philips Semiconductors
Objective specification
CAN controller interface
BLOCK DIAGRAM
PCA82C250
Fig.1 Block diagram.
PINNING SYMBOL TxD GND VCC RxD Vref CANL CANH Rs PIN 1 2 3 4 5 6 7 8 ground supply voltage receive data output reference voltage output LOW level CAN voltage input/output HIGH level CAN voltage input/output slope resistor input Fig.2 Pin configuration. DESCRIPTION transmit data input
September 1994
7-70
Philips Semiconductors
Objective specification
CAN controller interface
FUNCTIONAL DESCRIPTION The PCA82C250 is the interface between the CAN protocol controller and the physical bus. It is primarily intended for high-speed applications (up to 1 Mbaud) in cars. The device provides differential transmit capability to the bus and differential receive capability to the CAN controller. It is fully compatible with the "ISO/DIS 11898" standard. A current limiting circuit protects the transmitter output stage against short-circuit to positive and negative battery voltage. Although the power dissipation is increased during this fault condition, this feature will prevent destruction of the transmitter output stage. If the junction temperature exceeds a value of approximately 160 °C, the limiting current of both transmitter outputs is decreased. Because the transmitter is responsible for the major part of the power dissipation, this will result in a reduced power dissipation and hence a lower chip temperature. All other parts of the IC will remain in operation. The thermal protection is particularly needed when a bus line is short-circuited. The CANH and CANL lines are also protected against electrical transients which may occur in an automotive environment. Pin 8 (Rs) allows three different modes of operation to be selected: high-speed, slope control or standby. Table 1 Truth table of CAN transceiver. SUPPLY 4.5 to 5.5 V 4.5 to 5.5 V 0.75VCC X CANH HIGH floating floating floating floating if VRs > 0.75VCC CANL LOW floating floating floating floating if VRs > 0.75VCC
PCA82C250
For high-speed operation, the transmitter output transistors are simply switched on and off as fast as possible. In this mode, no measures are taken to limit the rise and fall slope. Use of a shielded cable is recommended to avoid RFI problems. The high-speed mode is selected by connecting pin 8 to ground. For lower speeds or shorter bus length, an unshielded twisted pair or a parallel pair of wires can be used for the bus. To reduce RFI, the rise and fall slope should be limited. The rise and fall slope can be programmed with a resistor connected from pin 8 to ground. The slope is proportional to the current output at pin 8. If a HIGH level is applied to pin 8, the circuit enters a low current standby mode. In this mode, the transmitter is switched off and the receiver is switched to a low current. If dominant bits are detected (differential bus voltage >0.9 V), RxD will be switched to a LOW level. The microcontroller should react to this condition by switching the transceiver back to normal operation (via pin 8). Because the receiver is slow in standby mode, the first message will be lost.
BUS STATE dominant recessive recessive recessive recessive
RxD 0 1 X X X
Table 2 Rs (pin 8) summary. CONDITION FORCED AT Rs VRs > 0.75VCC -10 µA < IRs < -200 µA VRs < 0.3VCC MODE standby slope control high-speed RESULTING VOLTAGE OR CURRENT AT Rs IRs < |10 µA| 0.4VCC < VRs < 0.6VCC IRs < -500 µA
September 1994
7-71
Philips Semiconductors
Objective specification
CAN controller interface
PCA82C250
LIMITING VALUES In accordance with the Absolute Maximum Rating System (IEC 134). All voltages are referenced to pin 2; positive input current. SYMBOL VCC Vn V6,7 Vtrt Tstg Tamb Tvj Note 1. In accordance with "IEC 747-1". An alternative definition of virtual junction temperature Tvj is: Tvj = Tamb + Pd × Rth vj-amb, where Rth vj-amb is a fixed value to be used for the calculation of Tvj. The rating for Tvj limits the allowable combinations of power dissipation (Pd) and ambient temperature (Tamb). HANDLING Classification A: human body model; C = 100 pF; R = 1 500 ; V = ±2 000 V. Classification B: machine model; C = 200 pF; R = 0 ; V = ±200 V. QUALITY SPECIFICATION Quality specification "SNW-FQ-611 part E" is applicable and can be found in the "Quality reference pocket-book" (ordering number 9398 510 34011). THERMAL CHARACTERISTICS SYMBOL Rth j-a PCA82C250 PCA82C250T PARAMETER thermal resistance from junction to ambient in free air 100 160 K/W K/W VALUE UNIT PARAMETER supply voltage DC voltage at pins 1, 4, 5 and 8 DC voltage at pins 6 and 7 transient voltage at pins 6 and 7 storage temperature operating ambient temperature virtual junction temperature note 1 0 V < VCC < 5.5 V; no time limit see Fig.8 CONDITIONS MIN. -0.3 -0.3 -8.0 -150 -55 -40 -40 MAX. +9.0 VCC + 0.3 +18.0 +100 +150 +125 +150 V V V V °C °C °C UNIT
September 1994
7-72
Philips Semiconductors
Objective specification
CAN controller interface
PCA82C250
CHARACTERISTICS VCC = 4.5 to 5.5 V; Tamb = -40 to +125 °C; RL = 60 ; I8 > -10 µA; unless otherwise specified. All voltages referenced to ground (pin 2); positive input current; all parameters are guaranteed over the ambient temperature range by design, but only 100% tested at +25 °C. SYMBOL Supply I3 supply current dominant; V1 = 1 V recessive; V1 = 4 V; R8 = 47 k recessive; V1 = 4 V; V8 = 1 V standby; Tamb < 90 °C; note 1 DC bus transmitter VIH VIL IIH IIL V6,7 ILO V7 V6 V6,7 HIGH level input voltage LOW level input voltage HIGH level input current LOW level input voltage recessive bus voltage output recessive output dominant V1 = 4 V V1 = 1 V V1 = 4 V; no load -5 V < (V6,V7) < 18 V CANH output voltage CANL output voltage difference between output voltage at pins 6 and 7 V1 = 1 V V1 = 1 V V1 = 1 V V1 = 1 V; RL = 45 ; VCC 4.9 V V1 = 4 V; no load Isc7 Isc6 short-circuit CANH current short-circuit CANL current V7 = -5 V; VCC 5 V V7 = -5 V; VCC = 5.5 V V 6 = 18 V 0.7VCC -0.3 -200 100 2.0 -2 -5 2.75 0.5 1.5 1.5 -500 - - - -1.0 -7 V < (V6, V7) < 12 V; not standby mode -7 V < (V6, V7) < 12 V; not standby mode see Fig.5 I4 = -100 µA I4 = 1 mA I4 = 10 mA -1.0 0.9 1.0 - 0.8VCC 0 0 5 7-73 - - - - - - - - - - - - - - - - - - - 150 - - - - VCC + 0.3 V 0.3VCC +30 600 3.0 +1 +12 4.5 2.25 3.0 - +50 105 120 160 V µA µA V mA mA V V V V mV mA mA mA - - - - - - - 100 70 14 18 170 mA mA mA µA PARAMETER CONDITIONS MIN. TYP. MAX. UNIT
off-state output leakage current -2 V < (V6,V7) < 7 V
DC bus receiver: V1 = 4 V; pins 6 and 7 externally driven; -2 V < (V6, V7) < 7 V; unless otherwise specified Vdiff(r) differential input voltage (recessive) differential input voltage (dominant) differential input hysteresis HIGH level output voltage (pin 4) LOW level output voltage (pin 4) CANH, CANL input resistance 0.5 0.4 5.0 5.0 - VCC 0.2VCC 1.5 25 V V V V mV V V V k
Vdiff(d)
Vdiff(hys) VOH VOL Ri September 1994
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