Order this document by MC34058/D HEX EIA–485 TRANSCEIVER with THREE–STATE OUTPUTS The Motorola MC34058/9 Hex Transceiver is composed of six driver/receiver combinations designed to comply with the EIA–485 standard. Features include three–state outputs, thermal shutdown for each driver, and current limiting in both directions. This device also complies with EIA–422 and CCITT Recommendations V.11 and X.27. The devices are optimized for balanced multipoint bus transmission at rates to 20 MBPS (MC34059). The driver outputs/receiver inputs feature a wide common mode voltage range, allowing for their use in noisy environments. The current limit and thermal shutdown features protect the devices from line fault conditions. The MC34058/9 is available in a space saving 7.0 mm 48 lead surface mount quad package designed for optimal heat dissipation. • Meets EIA–485 Standard for Party Line Operation • • • • • • • • • • SEMICONDUCTOR TECHNICAL DATA 48 1 Meets EIA–422A and CCITT Recommendations V.11 and X.27 FTA SUFFIX PLASTIC PACKAGE CASE 932 (Thin QFP) Operating Ambient Temperature: 0°C to +70°C Common Mode Driver Output/Receiver Input Range: –7.0 to +12 V Positive and Negative Current Limiting Transmission Rates to 14 MBPS (MC34058) and 20 MBPS (MC34059) Driver Thermal Shutdown at 150°C Junction Temperature ORDERING INFORMATION Thermal Shutdown Active Low Output Single + 5.0 V Supply, ±10% Device Low Supply Current MC34058FTA Compact 7.0 mm 48 Lead TQFP Plastic Package MC34059FTA Operating Temperature Range Package TA = 0° to +70°C TQFP–48 Representative Block Diagram TTL/CMOS Data Direction Control #1 TSD DR Thermal Shutdown Thermal Shutdown RE DE OB OA D To Cable #2 #3 (Same as #1) (Same as #1) #4 #5 (Same as #1) (Same as #1) TTL/CMOS Data RO Direction Control TTL/CMOS Data RE DE DI #6 TSD OB To Cable OA D This device contains 1,399 active transistors. Motorola, Inc. 1996 MOTOROLA ANALOG IC DEVICE DATA Rev 1 1 MC34058 MC34059 MAXIMUM RATINGS ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ Rating Symbol Value Unit VCC – 0.5, 7.0 Vdc Input Voltage (Driver Data, Enables) Vin 7.0 Vdc Applied Driver Output Voltage When in Three–State Condition (VCC = 5.0 V) VZ –10, 14 Vdc Applied Driver Output Voltage When VCC = 0 V VX ±14 Vdc Output Current IO Self Limiting – Tstg – 65, 150 °C Power Supply Voltage Storage Temperature NOTE: Devices should not be operated at these limits. The “Recommended Operating Conditions” provides for actual device operation. RECOMMENDED OPERATING CONDITIONS (All limits are not necessarily functional concurrently.) ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁ Characteristic Symbol Min Typ Max Unit VCC 4.5 5.0 5.5 Vdc Input Voltage (All Inputs Except Receiver Inputs) Vin 0 – VCC Vdc Driver Output Voltage in Three–State Condition, Receiver Inputs, or When VCC = 0 V VCM –7.0 – 12 Vdc Driver Output Current (Normal Data Transmission) IO – 60 – 60 mA Operating Ambient Temperature TA 0 – 70 °C Power Supply Voltage ELECTRICAL CHARACTERISTICS (TA = 25°C, VCC = 5.0 V ± 10%) Characteristic Symbol Min Typ Max Unit ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ DRIVER CHARACTERISTICS Output Voltage Single Ended, IO = 0 Differential, Open Circuit (IO = 0) Differential, RL = 54 Ω Change in Differential Voltage (Note 1), RL = 54 Ω Differential, RL = 100 Ω Change in Differential Voltage (Note 1), RL = 100 Ω Common Mode Voltage, RL = 54 Ω Common Mode Voltage Change, RL = 54 Ω VO |VOD1| |VOD2| |∆VOD2| |∆VOD2A| |VOD2A| VOCM |∆VOCM| 0 1.5 1.5 – 2.0 – – – – – – – – – – – VCC – – 200 – 200 3.0 200 Vdc Vdc Vdc mVdc Vdc mVdc Vdc mVdc IOS – 250 – 250 Driver Data Inputs Low Level Voltage High Level Voltage Clamp Voltage (Iin = –18 mA) VILD VIHD VIKD – 2.0 –1.5 – – – 0.8 – – Thermal Shutdown Junction Temperature TJTS – 150 – °C Vth – – 0.36 100 200 – 1.0 – mVdc VH – – 200 – – VOHR VOLR 2.4 – – – – 0.4 Vdc IOSR IOLKR – – 45 – 85 20 mA µA ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ Output Current (Each Output) Short Circuit Current, –7.0 V ≤ VO ≤ 12 V mA Vdc RECEIVER CHARACTERISTICS Input Threshold RO = High RO = Low Input Loading (Driver Disabled) Hysteresis Output Voltage High (IOH = – 400 µA) Low (IOL = 4.0 mA) Output Short Circuit Current Output Leakage Current When in Three–State Mode NOTE: 2 U.L. mV 1. Input switched from low to high. MOTOROLA ANALOG IC DEVICE DATA MC34058 MC34059 ELECTRICAL CHARACTERISTICS (continued) (TA = 25°C, VCC = 5.0 V ± 10%) Characteristic Symbol Min Typ Max Unit ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ ÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁÁ ÁÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁÁ ÁÁÁ MISCELLANEOUS Enable Inputs Low Level Voltage High Level Voltage Clamp Voltage (Iin = –18 mA) Vdc VILE VIHE VIKE 0 2.0 –1.5 – – – 0.8 VCC – ICC – 18 28 VOHT VOLT 2.4 0 – – – 0.8 Propagation Delay – Input to Single Ended Output Input to Output – Low–to–High Input to Output – High–to–Low tPLH tPHD – – 10 11 20 20 Propagation Delay – Input to Differential Output Input Low–to–High Input High–to–Low tPLHD tPHLD – – 15 15 23 23 tDR, tDF – 9.0 10.7 tSK1 tSK2 tSK3 0 0 0 0.1 – – – 8.0 6.0 tSK7 tSK8 0 – 0.1 <4.0 – – Power Supply Current (Total Package, All Outputs Open, Enabled or Disabled) Thermal Shutdown Output Voltage High Low mA Vdc TIMING CHARACTERISTICS – DRIVER ns ns Differential Output Transition Time Skew Timing |tPLHD – tPHLD| for Each Driver Maximum – Minimum tPLHD Within a Package Maximum – Minimum tPHLD Within a Package MC34058 Skew Timing MC34059 |tPLHD – tPHLD| for Each Driver Propagation Delay Difference Between Any Two Drivers (Same Package or Different Packages at Same VCC and TA) Enable Timing Single Ended Outputs Enable to Active High Output Enable to Active Low Output Active High to Disable Active Low to Disable Differential Outputs Enable to Active Output Enable to Three–State Output ns ns ns ns tPZH tPZL tPHZ tPLZ – – – – 15 25 12 10 40 40 25 25 tPZD tPDZ – – – – 40 25 tPLHR tPHLR – – 16 16 23 23 tSK4 tSK5 tSK6 0 0 0 1.0 – – – 3.0 3.0 tSK9 – <5.0 – TIMING CHARACTERISTICS – RECEIVER Propagation Delay Input to Output – Low–to–High Input to Output – High–to–Low Skew Timing |tPLHR – tPHLR| for Each Receiver Maximum – Minimum tPLHR Within a Package Maximum – Minimum tPHLR Within a Package Skew Timing Propagation Delay Difference Between Any Two Receivers in Different Packages at Same VCC and TA (MC34059 Only) Enable Timing Single Ended Outputs Enable to Active High Output Enable to Active Low Output Active High to Disable Active Low to Disable MOTOROLA ANALOG IC DEVICE DATA ns ns ns ns tPZHR tPZLR tPHZR tPLZR – – – – 15 25 12 10 22 30 25 25 3 MC34058 MC34059 Block Diagram and Pinout Gnd 48 DE6 RE6 DI6 RO6 47 46 45 44 VCC 43 VCC 42 DR5 RE5 DE5 Gnd Gnd 41 40 39 38 37 #5 Gnd 2 OA6 3 OB6 4 D 1 D Gnd #6 36 Gnd 35 OA5 MC34058/9 34 OB5 33 DR4 #4 DR1 5 OA1 6 32 OA4 31 OB4 D OB1 7 Thermal Shutdown Indicator D #1 30 DE4 8 29 RE4 RE1 9 28 OB3 OB2 10 27 OA3 OA2 11 26 Gnd Gnd 12 25 Gnd D D DE1 #3 #2 13 14 15 16 17 18 19 20 21 22 23 24 Gnd Gnd DE2 RE2 DR2 VCC VCC DR3 RE3 DE3 TSD Gnd PINOUT SUMMARY 4 OA NonInverting Output/Input DE Driver Enable, Active High (TTL) OB Inverting Output/Input RE Receiver Enable, Active Low (TTL) DR Driver Input/Receiver Output (TTL) TSD Thermal Shutdown Indicator DI6 #6 Driver Input (TTL) VCC Connect 4 Pins to 5.0 V, ± 10% RO6 #6 Receiver Output (TTL) Gnd Connect 12 Pins to Circuit Ground MOTOROLA ANALOG IC DEVICE DATA MC34058 MC34059 Figure 1. VOD and VOS Test Circuit VCC RL/2 Vin (0.8 or 2.0 V) VOD2, A RL/2 VOS Figure 2. VOD and VCM Test Circuit VCC 375 Vin (0.8 or 2.0 V) VOD2, A 58 VCM (+12 to ±7.0 V) 375 Figure 3. VOD AC Test Conditions VCC Vin 54 50 pF 3.0 V 1.5 V 1.5 V 0V tPLHD VOD S.G. tPHLD OAX 50% 50% VOD tdr tdr Figure 4. VOH and VOL AC Test Conditions 3.0 V 1.5 V 2.3 V VCC Vin 1.5 V tPLH 0V tPHL 27 Output S.G. 15 pF 3.0 V 3.0 V 3.0 V OBX tPLH MOTOROLA ANALOG IC DEVICE DATA 3.0 V OAX VOL VOH tPHL 5 MC34058 MC34059 Figure 5. VOH versus IOH Figure 6. VOL versus IOL 4.6 1.1 1.0 4.4 VOL (V) VOH (V) 0.9 4.2 4.0 0.8 0.7 3.8 3.6 – 80 0.6 – 60 – 40 – 20 0 0.5 20 0 10 20 30 40 50 60 70 IOH (mA) IOL (mA) Figure 7. VOD versus IOL Figure 8. Input Characteristics of OAX and OAB 80 0.4 4.0 0.3 INPUT CURRENT (mA) VODH VOD (V) 2.0 0 – 2.0 VODL – 50 0 50 100 IOD (mA) Description The MC34058/9 is a differential line driver designed to comply with EIA–485 Standard for use in balanced digital multipoint systems containing multiple drivers. The drivers also comply with EIA–422–A and CCITT Recommendations V.11 and X.27. Positive and negative current limiting of the drivers meet the EIA–485 requirement for protection from damage in the event that two or more drivers try to transmit simultaneously on the same cable. Data rates in excess of 10 MBPS are possible, depending on the cable length and cable characteristics. Only a single power supply, 5.0 V ± 10% is required. ā Driver Inputs The driver inputs and enable logic determine the state of the outputs in accordance with Table 1. The driver inputs have 6 OAX_lin(mA) 0.1 OBX_lin(mA) 0 – 0.1 – 0.2 – 0.3 – 4.0 –100 0.2 – 0.4 – 10 – 5.0 0 5.0 10 15 INPUT VOLTAGE (V) a nominal threshold of 1.2 V, and the voltage must be kept within the range of 0 V to VCC for proper operation. If the voltage is taken more than 0.5 V below ground or above VCC, excessive currents will flow and proper operation of the drivers will be affected. An open Pin is equivalent to a logic high, but good design practices dictate that inputs should never be left open. The inputs are TTL type and their characteristics are unchanged by the state of the enable pins. Driver Outputs Each output (when active) will be a low or a high voltage, depending on the input state and the load current (see Tables 1, 2 and Figures 2 and 3). The graphs apply to each driver, regardless of how many other drivers within the package are supplying load current. MOTOROLA ANALOG IC DEVICE DATA MC34058 MC34059 Table 1. Driver Truth Table Enables Outputs Driver Data Inputs DEX REX OAX OBX H H H H L H L H H L X L H Z Z X H L Not Defined Not Defined The outputs will be in a high impedance state when: a) The Enable inputs are set according to Table 1; b) The junction temperature exceeds the trip point of the thermal shutdown circuit. When in this condition, the output’s source and sink capability are shut off, and a leakage current of less than 20 µA will flow. Disabled outputs may be taken to any voltage between –7.0 V and 12 V without damage to internal circuitry. The drivers are protected from short circuits by two methods: a) Current limiting is provided at each output, in both the source and sink direction, for shorts to any voltage within the 12 V to –7.0 V range, with respect to circuit ground. The short circuit current will flow until the fault is removed, or until the thermal shutdown activates. The current limiting circuit has a negative temperature coefficient and requires no resetting upon removal of the fault condition. b) A thermal shutdown circuit disables the outputs when the junction temperature reaches +150°C, ± 20°C. The thermal shutdown circuit has a hysteresis of ∼ 12°C to prevent oscillations. When this circuit activates, the output stage of each driver is put into the high impedance mode, thereby shutting off the output currents. However, the remainder of the internal circuitry remains biased and the outputs will become active once again as the IC cools down. Receiver Inputs The receiver inputs and enable logic determine the state of the receiver outputs in accordance with Table 2. Each receiver input pair has a nominal differential threshold of at most 200 mV (Pin OAX with respect to OBX) and a common mode voltage range of –7.0 V and 12 V must be maintained for proper operation. A nominal hysteresis of 100 mV is typical. The receiver input characteristics are shown in Figure 8. When the inputs are in the high impedance state, they remain capable of the common mode voltage range of –7.0 V to 12 V. Receiver Outputs The receiver outputs are TTL type outputs and act in accordance with Table 2. Enable Logic Each driver output is active when the Driver Enable input is true according to Table 1. Each receiver output is active when the Receiver Enable input is true according to Table 2. The Enable inputs have a nominal threshold of 1.2 V and their voltage must be kept within the range of 0 V and VCC for proper operation. If the voltage is taken more than 0.5 V below ground or above VCC, excessive currents will flow and proper operation of the drivers will be affected. An open pin is equivalent to a logic high, but good design practices dictate that inputs should never be left open. The enable inputs are TTL compatible. Since the same pins are used for driver input and receiver output, care must be taken to make sure that DEX and REX are not both enabled. This may result in corruption of both the transmitted and received data. Table 2. Receiver Truth Table Receiver Data Inputs Enables Outputs OAX–OBX DEX REX DRX ≥ + 200 mV L L H ≤ – 200 mV L L L X L H Z X H L Not Defined APPLICATIONS The MC34058/9 was designed to meet EIA/TIA–422 and EIA/TIA–485 standards. EIA/TIA–422 specifies balanced point–to–point transmission with the provision for multiple receivers on the line. EIA/TIA–485 specifies balanced point–to–point transmission and allows for multiple drivers and receivers on the line. Refer to EIA/TIA documents for more details. Figure 9 shows a typical EIA/TIA–422 example. Figure 10 shows a typical EIA/TIA–485 example. Figure 9. Typical EIA/TIA–422 Application RT 100 Ω MOTOROLA ANALOG IC DEVICE DATA 7 MC34058 MC34059 Figure 10. Typical EIA/TIA–485 Application RT 120 Ω RT 120 Ω EIA/TIA–422 specifications require the ability to drive at least 10 receivers of input impedance of greater than or equal to 4.0 KΩ plus the 100 Ω termination resistor. This protocol was intended for unidirectional transmission. EIA/TIA–485 is capable of bidirectional transmission by allowing multiple drivers and receivers on the same twisted pair segment. The loading of the twisted pair segment can be up to 32 Unit Loads (U.L.) plus the two 120 Ω terminating resistors. The U.L. definition is shown in Figure 11. where: θja = package thermal resistance (see Appendix A) TJmax = Maximum Junction Temperature. Since the thermal shutdown feature has a trip point of 150°C ± 20°, TJmax is selected to be +130°C. TA = Ambient Operating Temperature. The power generated within the package is then; PD Figure 11. TIA/EIA–485 Unit Load Definition + NJƪǒ V CC Ii ÇÇÇÇÇÇÇÇÇÇ ÇÇÇÇÇÇÇÇÇÇ ÇÇÇÇÇÇÇÇÇÇ ÇÇÇÇÇÇÇÇ ÇÇÇÇÇÇÇÇÇÇ ÇÇÇÇÇÇÇÇ (each_driver).. +1.0 mA –7.0 V – 3.0 V Vi +5.0 V V +12 V – 0.8 mA Calculating Power Dissipation for the MC34058/9 Hex–Transceiver. The operational temperature range is listed as 0°C to 70°C to satisfy both EIA/TIA–485 and EIA/TIA–422 specifications. However, a lower ambient temperature may be required depending on the specific board layout and/or application. Using a first order approximation for heat transfer, the maximum power which may be dissipated by the package is determined by (see Appendix A for more details); P 8 + Dmax T – T Jmax A θja OL · I 6 OL 6 ) Nj NJƪǒ – V Ǔ ƫ OH 1 V · I CC OH – V ) VCC · ICCQ 1 ) VOL · I Ǔ ƫ OH 6 · I 1 OH 6 Nj OL 1 ) .. ) [2] As indicated in the equation, the part of Equation 2 consisting of IOH , VOH , IOL and VOL must be calculated for each of the drivers and summed for the total power dissipation estimate. The last term can be considered the quiescent power required to keep the IC operational and is measured with the drivers idle and unloaded. The VOH and VOL terms can be determined from the output current versus output voltage curves which provide driver output characteristics. Example 1 estimates thermal performance based on current requirements. [1] MOTOROLA ANALOG IC DEVICE DATA MC34058 MC34059 Example 1. Balanced and Unbalanced Operation IOL = 50 mA and IOH = ± 50 mA for each driver. VCC = 5.0 V. How many drivers can be used? (Typical power supply current ICCQ = 18 mA.) Solution: ICCQ = 0.018 A I · V , and is equal to PQ 0.09 W. The quiescent power is given by: PQ CC CCQ Unbalanced Operation: Balanced Operation: To determine the amount of power dissipated by each To determine the amount of power dissipated by each output stage we need to know the single–ended output output stage we need to know the differential output voltage voltage for the output current required. Figures 5 and 6 for the output current required. Figure 7 shows that for IOH shows that for an IOH and IOL of ± 50 mA, and IOL differential of 50 mA, VODH and VODL are: + V OD + |3.0|, and I ǒ OL + V + |IOH| + IOut + 0.050 A. + IOut · VCC – VOD P + 0.10 W. DrvB DrvB Ǔ + 3.9 V V OL + 0.895 V Ǔ ǒ And the power dissipated by each driver is calculated by; V – V · |I | V · I P DrvU CC OH OH OL OL and equal to P 0.10 W. DrvU + + And the power dissipated by each driver is given by; P OH and equal to ) (For this example, balanced operation is assumed.) Summing the quiescent and driver power for 6 transceivers operating in a package produces; PDTotal = PQ + 6 ⋅ PDrvB, and equal to PDTotal = 0.69 W. For the MC34058/9, the thermal resistance is capable of a wide range. The ability of the package to dissipate power depends on board type and temperature, layout and ambient temperature (see Appendix A). For the purposes of this example the thermal resistance can range from 40°C/W to 100°C/W; θja = j, j = 40, 60, .. 100°C/W. Varying the ambient operating temperature TA = 25, 30, .. 85°C; specifying a maximum junction temperature to avoid thermal shutdown TJmax = 130°C; and using the first order approximation for maximum power dissipation; T –T Jmax A P , T Dmax qja A qja + ǒ Ǔ produces a set curves that can be used to determine a Safe Operating Area for the specific application. PDTotal is graphed with PDmax to provide a reference. Graph of Maximum Power Dissipation Possible for a Particular θja and Ambient Temperature 3.0 PDmax (θja ), TA 40 WATTS 2.5 2.0 PDmax (θja60), TA PDmax (θja ), TA 80 1.5 1.0 *SOA 0.5 PDmax (θja ), TA 100 PDTotal 0 20 30 40 50 60 70 80 90 TA (°C) * Safe Operating Area (SOA), is an operating power, PDTotal, less than PDmax. So all the drivers in the package can be used if the thermal resistance and/or the ambient temperature is low enough. MOTOROLA ANALOG IC DEVICE DATA 9 MC34058 MC34059 Appendix A. Optimizing the Thermal Performance of the MC34058/9 Figure 12. Electrical Model of Package Heat Transfer Ambient Temperature RCA (leads–to–board) combination in Figure 12. This path provides the most effective way of removing heat from the device provided that there is a viable temperature potential (i.e. heat sinking source) to conduct towards. However, if it is not properly considered in the system design, the other paths, (Rjcd + Rcdb) and (Rjcu + Rca) attain greater importance and must be more carefully considered. So Equation 1, modified to reflect a more complete heat transfer model becomes; RJCU T Device Junction 1 1 ) 1 Rjcd Rjlb RJCD AAA RCDB RLB T B · An equivalent electrical circuit for the thermal model for the MC34058/9 package is shown in Figure 12. It is a simplified model that shows the dominant means of heat transfer from the thermally enhanced 48–ld package used for the MC34058/9. The model is a first order approximation and is intended to emphasize the need to consider thermal issues when designing the IC into any system. It is however customary to use similar models and Equation 1 to estimate device junction temperatures. Equation 1 is the common means of using the thermal resistance of a package to estimate junction temperature in a particular system. T J + ǒ P D · qjx Ǔ) T A [1] The term θjx in Equation 1 is usually quoted as a øja value in °C/Watt. However, since the 48–ld package for the MC34058/9 has been thermally enhanced to take advantage of other heat sinking potentials, it must be modified. θjx must actually be considered a composite of all the heat transfer paths from the chip. That is, the three dominant and parallel paths shown in Figure 12. Of those three paths, potentially the most effective is the corner package leads. This is because these corner leads have been attached to the flag on which the silicon die is situated. These pins can be connected to circuit board ground to provide a more efficient conduction path for internal package heat. This path is modeled as the Rjl (junc tion–to–leads ) and Rlb 10 )AAA Rjca Rjca 1 1 ) 1 Rjcd Rjlb Board Temperature ȣȧ Ȥ ȡȧ ȣȧ) Ȣ Ȥ ȡȧ ȣȧ) Ȣ Ȥ + TA · 1 1 ) 1 Rjcd Rjlb IPD 5.0 A RJL J ȡȧ Ȣ [2] ) PDISS · qja Rjca where; TJ= Junction Temperature TA = Ambient Temperature TB = Board Temperature PDISS = Device Power and θja = Total Thermal Resistance and is composed the parallel combination of all the heat transfer paths from the package. While Equation 2 is still only a first order approximation of the heat transfer paths of the MC34058/9, at least now it includes consideration for the most effective heat transfer path for the MC34058/9; the board to which the device is soldered. The modified equation also better serves to explain how external variables, namely the board and ambient temperatures, affect the thermal performance of the MC34058/9. Methods of removing heat via the flag connected pins can be classified into two means; conduction and convection. Radiation is omitted as the contribution is small compared to the other means. Conduction is by far the best method to draw heat away from the MC34058/9 package. This is best accomplished by using a multilayer board with generous ground plane. In this case, the flag connected pins can be connected directly to the ground plane to maximize the heat transfer from the package. Figure 13 shows the results of thermal measurements of a board with an external ground plane (the actual ground area was approximately 6 1/4 in2). The thermal leads are connected to the board ground plane per the recommended strategy. MOTOROLA ANALOG IC DEVICE DATA MC34058 MC34059 Figure 14A. Thermal Resistance (θja) for Board Without Ground Plane Figure 13. Thermal Resistance (θja) for Board with Large External Ground Plane 120 55 110 No Radiators 50 θja (° C/W) θja (° C/W) 100 45 40 90 Masked Radiators* 80 70 35 60 Exposed Radiators* 50 30 0 100 200 300 400 500 0 600 200 400 600 800 1200 1000 AIR SPEED (LINEAR FT/MIN) AIR SPEED (LINEAR FT/MIN) θjc for the package on this board is 25 ± 20% depending on the location of the package on the board. Figure 14B. Layout Used for Thermal Resistance Measurements in Figure 14A * Masked radiators were covered by a solder mask. Exposed radiators were bare copper. Figure 15. Placement of Thermal Vias to Enhance Heat Transfer to Ground Plane 8 (mm) w (mm) w (mm) l (mm) 8 (mm) Copper Radiators l (mm) Copper Radiators Figure 14A on the other hand shows the result of a single layer board without an internal ground plane. The graphs show that even though there are radiators of substantial area surrounding the package, substantial degredation of thermal performance is evident (Figure 14B shows the layout used for the measurements in Figure 14A). Comparing Figures 13 and 14A shows almost a 2:1 improvement for the strategy involving the external ground plane. It is clear from Figures 13, 14A and Example 1, that if an application is to use all the device drivers, preparations to assure adequate thermal performance of the system must be taken. MOTOROLA ANALOG IC DEVICE DATA If an extensive external ground plane is unavailable, and only an internal ground plane is available, the thermal performance of the device can still be improved by providing thermal vias to connect the radiators to the internal ground plane. Figure 15 shows a proposed scheme for thermal vias (contact board manufactures for specifics about the thermal performance of their products and possible enhancements). The thermal resistance for this structure on 1.0 oz. Copper connecting each of the four radiators to an internal ground plane and provide an estimated thermal resistance of approximately 5.0°C/W. The vias used in the estimate had 80 mil diameters, on 100 mil centers and a 1.0 mil copper thickness. 11 MC34058 MC34059 O 4 . 2 9 0 0Z ( D A A 4 3 E T – 1 2 2 1 3 2 U 5 V Z – A – T – , D . 2 0 0Z ( 0 . A S E A D M E T . 0 S M E o c a t e l d d s o o 8 T A E ) 8 r s i r i e i i r r O A A C ( 0 0 T . P T0C C o u f s b s c a t n o t B R O G E C J W H 8A & L S– S (U T l i i h e . a t s g l u 0 I a t c e t h O a a e v i o o a n . i r b l t a M o m f u w t 0 0 D N e i l s l o n a f t a y 3 s l y e i i t s y i MFAX: [email protected] – TOUCHTONE 602–244–6609 INTERNET: http://Design–NET.com ◊ T E r a d o A y i n a r e s d t o i o e f n f u n o d a t n u , d e f r e c s g i r i l r h i a i m M E N NOTES: AND TOLERANCING PER ANSI –1 DIMENSIONING U Y14.5M, 1982. 2 CONTROLLING DIMENSION: MILLIMETER. Y 3 DATUM PLANE –AB– IS LOCATED AT BOTTOM OF LEAD AND IS COINCIDENT WITH THE LEAD WHERE THE LEAD EXITS THE PLASTIC BODY AT THE BOTTOM OF THE PARTING LINE. 4 DATUMS –T–, –U–, AND –Z– TO BE DETERMINED AT DATUM PLANE –AB–. 5 DIMENSIONS S AND V TO BE DETERMINED AT SEATING PLANE –AC–. 6 DIMENSIONS A AND B DO NOT INCLUDE MOLD PROTRUSION. ALLOWABLE PROTRUSION IS 0.250 (0.010) PER SIDE. DIMENSIONS A AND B DO INCLUDE MOLD MISMATCH AND ARE DETERMINED AT DATUM PLANE –AB–. 7 DIMENSION D DOES NOT INCLUDE DAMBAR DAMBAR PROTRUSION SHALL A PROTRUSION. E NOT CAUSE THE D DIMENSION TO EXCEED 0.350 (0.014). 8 MINIMUM SOLDER PLATE THICKNESS SHALL BE 0.0076 (0.0003). 9 EXACT SHAPE OF EACH CORNER IS OPTIONAL. A t f l / e l c r , s o c I INCHES MIN MAX 0.276 BSC 0.138 BSC Z0.276 BSC– 0.138 BSC 0.055 0.063 0.007 0.011 0.053 0.057 0.007 0.009 0.020 BASIC 0.002 0.006 0.004 0.008 C 0.020 0.028 12 _REF 0.004 0.006 0.010 BASIC 1_ 5_ 0.006 0.010 0.354 BSC 0.177 BSC 0.354 A BSC N E 0.177 BSC ( 0.0080 REF . 0.039 REF 0 1 0 ) Q_ Z I K L A E X A – v t d c o s / ) E A H o w t o r e a c h USA / EUROPE / Locations Not Listed: Motorola Literature Distribution; P.O. Box 20912; Phoenix, Arizona 85036. 1–800–441–2447 or 602–303–5454 12 U 0 F D t p 0 0 – N i – D MILLIMETERS DIM MIN MAX A 7.000 BSC A1 3.500 BSC 7.000 BSC – ,B – B1 3.500 BSC C 1.400 1.600 I LD 0.170 0.270 Y E 1.350 1.450 F 0.170 0.230 0.500 BASIC – UG H 0.050 0.150 0 0 J 3 0.090) 0.200 A K 0.500 0.700 M 12 _REF N 0.090 0.160 P 0.250 BASIC 1M 5_ _ T T QO R 0.150 0.250 S 9.000 BSC S1 4.500 BSC V A U G E 9.000 BSC P L V1 4.500 BSC . 2 W5 0 REF 0.200 X 1.000 REF M_ ÉÉÉ ÇÇÇÇ ÇÇÇÇ ÉÉÉ ÇÇÇÇ ÉÉÉ t e e t s h p . T B o h p a u t p r n r o p 0 0 – C 0 E X B A L – G M t s d m o a o a a M O IP T 1 1 0 A B – S – E 4 – S 4 A A V 1 N 6 – B B I 7 3 T L 1 8 1 – T FTA SUFFIX PLASTIC PACKAGE CASE 932–02 (Thin QFP) 0 . ISSUE 0 0D 8 ) X 0 U e t i D r s m i p s g r a s p e c i f o r e a p r o d u c d e d t o . S h o e m p l o y r e c t l y g e n t r a t i v e h o t n u y i f c t c h s s u e u d s l e o e A t d a a c a p t n t u r p B i a t s : JAPAN: Nippon Motorola Ltd.; Tatsumi–SPD–JLDC, 6F Seibu–Butsuryu–Center, 3–14–2 Tatsumi Koto–Ku, Tokyo 135, Japan. 03–81–3521–8315 ASIA/PACIFIC: Motorola Semiconductors H.K. Ltd.; 8B Tai Ping Industrial Park, 51 Ting Kok Road, Tai Po, N.T., Hong Kong. 852–26629298 *MC34058/D* MOTOROLA ANALOG IC DEVICE DATA MC34058/D s e o u s n r i s d i , r g c o c d d o i n