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MC34058 MC34059 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
HEX EIA-485 TRANSCEIVER with THREE-STATE OUTPUTS
SEMICONDUCTOR TECHNICAL DATA
48
1
* * * * * * * * * *
Meets EIA-422A and CCITT Recommendations V.11 and X.27 Operating Ambient Temperature: 0C to +70C 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 150C Junction Temperature Thermal Shutdown Active Low Output Single + 5.0 V Supply, 10% Low Supply Current Compact 7.0 mm 48 Lead TQFP Plastic Package
Device MC34058FTA MC34059FTA TA = 0 to +70C TQFP-48 FTA SUFFIX PLASTIC PACKAGE CASE 932 (Thin QFP)
ORDERING INFORMATION
Operating Temperature Range Package
Representative Block Diagram
Thermal Shutdown OB D #3 (Same as #1) #4 #5 (Same as #1) TTL/CMOS Data Direction Control TTL/CMOS Data RO RE DE DI #6 TSD D OB To Cable OA (Same as #1) (Same as #1) OA #2 To Cable
TTL/CMOS Data Direction Control
DR RE DE
#1 TSD
Thermal Shutdown
This device contains 1,399 active transistors.
(c) Motorola, Inc. 1996 Rev 1
MOTOROLA ANALOG IC DEVICE DATA
1
MC34058 MC34059
MAXIMUM RATINGS
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Power Supply Voltage VCC Vin VZ - 0.5, 7.0 7.0 Vdc Vdc Vdc Vdc - Input Voltage (Driver Data, Enables) Applied Driver Output Voltage When in Three-State Condition (VCC = 5.0 V) Applied Driver Output Voltage When VCC = 0 V Output Current -10, 14 14 VX IO Self Limiting - 65, 150 Storage Temperature Tstg C
NOTE: Devices should not be operated at these limits. The "Recommended Operating Conditions" provides for actual device operation.
Rating
Symbol
Value
Unit
RECOMMENDED OPERATING CONDITIONS (All limits are not necessarily functional concurrently.)
Characteristic Power Supply Voltage Symbol VCC Vin Min 4.5 0 Typ 5.0 - - - - Max 5.5 Unit Vdc Vdc Vdc mA C
Input Voltage (All Inputs Except Receiver Inputs) Driver Output Voltage in Three-State Condition, Receiver Inputs, or When VCC = 0 V
VCC 12
VCM IO
-7.0 - 60 0
Driver Output Current (Normal Data Transmission) Operating Ambient Temperature
60 70
TA
ELECTRICAL CHARACTERISTICS (TA = 25C, VCC = 5.0 V 10%)
Characteristic DRIVER CHARACTERISTICS Output Voltage Single Ended, IO = 0 Differential, Open Circuit (IO = 0) Differential, RL = 54 Change in Differential Voltage (Note 1), RL = 54 Differential, RL = 100 Change in Differential Voltage (Note 1), RL = 100 Common Mode Voltage, RL = 54 Common Mode Voltage Change, RL = 54 Output Current (Each Output) Short Circuit Current, -7.0 V VO 12 V Driver Data Inputs Low Level Voltage High Level Voltage Clamp Voltage (Iin = -18 mA)
Symbol
Min
Typ
Max
Unit
VO |VOD1| |VOD2| |VOD2| |VOD2A| |VOD2A| VOCM |VOCM| IOS
0 1.5 1.5 - 2.0 - - -
- - - - - - - - - - - -
VCC - - 200 - 200 3.0 200 250 0.8 - - -
Vdc Vdc Vdc mVdc Vdc mVdc Vdc mVdc mA
- 250 - 2.0 -1.5 -
Vdc
VILD VIHD VIKD
Thermal Shutdown Junction Temperature
TJTS
150
C
RECEIVER CHARACTERISTICS Input Threshold
RO = High RO = Low
Vth
Input Loading (Driver Disabled) Hysteresis
VH
- - 200 - - 2.4 - - -
- - 0.36 100 - -
200 - 1.0 - - 0.4 85 20
mVdc U.L. mV Vdc mA A
Output Voltage
High (IOH = - 400 A) Low (IOL = 4.0 mA)
VOHR VOLR
Output Short Circuit Current Output Leakage Current When in Three-State Mode
1. Input switched from low to high.
IOSR IOLKR
45 -
NOTE:
2
MOTOROLA ANALOG IC DEVICE DATA
MC34058 MC34059
ELECTRICAL CHARACTERISTICS (continued) (TA = 25C, VCC = 5.0 V 10%)
Characteristic MISCELLANEOUS Symbol Min Typ Max Unit
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Enable Inputs Low Level Voltage High Level Voltage Clamp Voltage (Iin = -18 mA) Vdc VILE VIHE VIKE ICC 0 2.0 -1.5 - - - - 0.8 VCC - 28 Power Supply Current (Total Package, All Outputs Open, Enabled or Disabled) Thermal Shutdown Output Voltage High Low 18 mA Vdc VOHT VOLT 2.4 0 - - - 0.8 TIMING CHARACTERISTICS - DRIVER Propagation Delay - Input to Single Ended Output Input to Output - Low-to-High Input to Output - High-to-Low Propagation Delay - Input to Differential Output Input Low-to-High Input High-to-Low Differential Output Transition Time ns tPLH tPHD - - - - - 0 0 0 0 - 10 11 15 15 20 20 23 23 ns tPLHD tPHLD tDR, tDF tSK1 tSK2 tSK3 tSK7 tSK8 9.0 0.1 - - 10.7 - 8.0 6.0 - - ns tPZH tPZL tPHZ tPLZ tPZD tPDZ - - - - - - 15 25 12 10 - - 40 40 25 25 40 25 ns ns 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 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 ns tPLHR tPHLR tSK4 tSK5 tSK6 tSK9 - - 0 0 0 - 16 16 1.0 - - <5.0 23 23 ns - 3.0 3.0 - ns ns 0.1 <4.0 ns tPZHR tPZLR tPHZR tPLZR - - - - 15 25 12 10 22 30 25 25
MOTOROLA ANALOG IC DEVICE DATA
3
MC34058 MC34059
Block Diagram and Pinout
Gnd 48
DE6 47
RE6 46
DI6 45
RO6 44
VCC 43
VCC 42
DR5 41
RE5 40
DE5 39
Gnd 38
Gnd 37
#5 D D #6 Gnd Gnd OA6 OB6 DR1 OA1 OB1 DE1 RE1 OB2 OA2 Gnd 1 2 3 4 #4 5 6 D 7 8 9 10 11 12 #2 D #1 D Thermal Shutdown Indicator 30 DE4 29 RE4 28 OB3 27 OA3 26 Gnd 25 Gnd #3 32 OA4 31 OB4 36 Gnd 35 OA5 34 OB5 33 DR4
MC34058/9
13 Gnd
14 Gnd
15 DE2
16 RE2
17 DR2
18 VCC
19 VCC
20 DR3
21 RE3
D 22 DE3
23 TSD
24 Gnd
PINOUT SUMMARY
OA OB DR DI6 RO6 NonInverting Output/Input Inverting Output/Input Driver Input/Receiver Output (TTL) #6 Driver Input (TTL) #6 Receiver Output (TTL) DE RE TSD VCC Gnd Driver Enable, Active High (TTL) Receiver Enable, Active Low (TTL) Thermal Shutdown Indicator Connect 4 Pins to 5.0 V, 10% Connect 12 Pins to Circuit Ground
4
MOTOROLA ANALOG IC DEVICE DATA
MC34058 MC34059
Figure 1. VOD and VOS Test Circuit
VCC
Vin (0.8 or 2.0 V)
RL/2 VOD2, A RL/2 VOS
Figure 2. VOD and VCM Test Circuit
VCC 375
Vin (0.8 or 2.0 V)
VOD2, A
58 375
VCM (+12 to 7.0 V)
Figure 3. VOD AC Test Conditions
VCC 1.5 V tPLHD tPHLD OAX 50% tdr tdr 50% VOD 3.0 V 1.5 V 0V
Vin 54 S.G. 50 pF VOD
Figure 4. VOH and VOL AC Test Conditions
2.3 V VCC Vin 27 Output S.G. 15 pF 3.0 V OAX OBX 3.0 V tPLH tPHL 3.0 V 3.0 V VOL 1.5 V tPLH 3.0 V 1.5 V tPHL 0V
VOH
MOTOROLA ANALOG IC DEVICE DATA
5
MC34058 MC34059
Figure 5. VOH versus IOH
4.6 4.4 4.2 4.0 3.8 3.6 - 80 1.1 1.0 0.9 VOH (V) VOL (V) 0.8 0.7 0.6 0.5
Figure 6. VOL versus IOL
- 60
- 40 IOH (mA)
- 20
0
20
0
10
20
30
40 IOL (mA)
50
60
70
80
Figure 7. VOD versus IOL
0.4 4.0 2.0 VOD (V) 0 - 2.0 VODL - 4.0 -100 - 50 0 IOD (mA) 50 100 INPUT CURRENT (mA) VODH 0.3 0.2
Figure 8. Input Characteristics of OAX and OAB
OAX_lin(mA) 0.1 OBX_lin(mA) 0 - 0.1 - 0.2 - 0.3 - 0.4 - 10 - 5.0 0 5.0 10 15
INPUT VOLTAGE (V)
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. Driver Inputs The driver inputs and enable logic determine the state of the outputs in accordance with Table 1. The driver inputs have
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.
6
MOTOROLA ANALOG IC DEVICE DATA
MC34058 MC34059
Table 1. Driver Truth Table Enables Driver Data Inputs
H L X X
Outputs REX
H H H L
DEX
H H L H
OAX
H L Z Not Defined
OBX
L H Z 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 A 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 +150C, 20C. The thermal shutdown circuit has a hysteresis of 12C 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 OAX-OBX
+ 200 mV - 200 mV X X
Enables DEX
L L L H
Outputs REX
L L H L
DRX
H L Z 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
MOTOROLA ANALOG IC DEVICE DATA
7
MC34058 MC34059
Figure 10. Typical EIA/TIA-485 Application
RT 120
RT 120
EIA/TIA-422 specifications require the ability to drive at least 10 receivers of input impedance of greater than or equal to 4.0 K plus the 100 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 terminating resistors. The U.L. definition is shown in Figure 11. Figure 11. TIA/EIA-485 Unit Load Definition
Ii
where: ja = package thermal resistance (see Appendix A) TJmax = Maximum Junction Temperature. Since the thermal shutdown feature has a trip point of 150C 20, TJmax is selected to be +130C. TA = Ambient Operating Temperature. The power generated within the package is then; PD
+
V
CC
-V
OH 1
*I
OH
1
) VOL
*I
*I 1
OL 1
) ..
(each_driver)..
)
V
CC
-V
+1.0 mA
OH 6
OH 6
)
[2]
- 0.8 mA
Calculating Power Dissipation for the MC34058/9 Hex-Transceiver. The operational temperature range is listed as 0C to 70C 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
CCCCCCCCCCCCC CCCCC CCCCCCCCCCCCC CCCCC CCCCCCCCCC CCCCCCCCCC
-7.0 V - 3.0 V +5.0 V +12 V
Vi
V
OL
*I 6
OL 6
) VCC * ICCQ
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.
+ Dmax
T
-T Jmax A ja
[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
OL
+ |IOH| + IOut + 0.050 A.
and equal to
V
OH
+ 3.9 V + +
V
OL
+ 0.895 V
And the power dissipated by each driver is given by;
+ IOut * VCC - VOD P + 0.10 W. DrvB
P DrvB
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
)
(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 40C/W to 100C/W; ja = j, j = 40, 60, .. 100C/W. Varying the ambient operating temperature TA = 25, 30, .. 85C; specifying a maximum junction temperature to avoid thermal shutdown TJmax = 130C; and using the first order approximation for maximum power dissipation; T -T Jmax A P ,T Dmax qja A qja
+
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 ja and Ambient Temperature
3.0 PDmax (ja ), TA 40 2.5 2.0 1.5 1.0 0.5 PDTotal 0 20 30 40 50 TA (C) PDmax (ja ), TA 100 60 70 80 90 PDmax (ja60), TA
WATTS
PDmax (ja ), TA 80
*SOA
* 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 (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; 1 1)1 Rjcd Rjlb 1 1)1 Rjcd Rjlb
RJCD
Ambient Temperature
RCA
RJCU
T
Device Junction
J
+TA *
)AAA
[2]
)Rjca ) PDISS * qja
RJL
IPD 5.0 A
RLB
RCDB
AAA
T
B
*
Rjca 1 1)1 Rjcd Rjlb
)Rjca
Board Temperature
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
+
P
D
* qjx
)TA
[1]
The term jx in Equation 1 is usually quoted as a oja 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. jx 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
where; TJ= Junction Temperature TA = Ambient Temperature TB = Board Temperature PDISS = Device Power and ja = 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.
10
MOTOROLA ANALOG IC DEVICE DATA
MC34058 MC34059
Figure 13. Thermal Resistance (ja) for Board with Large External Ground Plane
55 50 100 ja ( C/W) 45 40 35 30 0 100 200 300 400 500 600 AIR SPEED (LINEAR FT/MIN)
jc for the package on this board is 25 20% depending on the location of the package on the board.
Figure 14A. Thermal Resistance (ja) for Board Without Ground Plane
120 110 No Radiators ja ( C/W)
90 80 70 60 50 0 Exposed Radiators* 200 400 600 800 1000 1200 Masked Radiators*
AIR SPEED (LINEAR FT/MIN)
* Masked radiators were covered by a solder mask. Exposed radiators were bare copper.
Figure 14B. Layout Used for Thermal Resistance Measurements in Figure 14A
8 (mm)
Figure 15. Placement of Thermal Vias to Enhance Heat Transfer to Ground Plane
w (mm) w (mm) l (mm) Copper Radiators l (mm)
8 (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.
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 5.0C/W. The vias used in the estimate had 80 mil diameters, on 100 mil centers and a 1.0 mil copper thickness.
MOTOROLA ANALOG IC DEVICE DATA
11
MC34058 MC34059
O U T L I N E D I M E N
4
X
0 9 A
4 8
. A 1
2
0
0Z
(
FTA SUFFIX PLASTIC PACKAGE CASE 932-02 (Thin QFP) 0 . ISSUE D 8 0 0 ) D E T A P I
A L
B
T
3
7
1
3
6
- B B
T
-
-
U V
-
A
E
1
1 2 2 5
V
1
NOTES: 1 - DIMENSIONING AND TOLERANCING PER ANSI 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 A PROTRUSION. DAMBAR PROTRUSION SHALL 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. INCHES MIN MAX 0.276 BSC 0.138 BSC 0.276 - Z 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 BSC E A N 0.177 BSC ( 0.008 REF . 0 0.039 REF
1
3
2
4
- S 1 S
4 X
Z
- - T - , D E ) 0 A ( - T C 0 . U A T
0
.
2 G
0
0Z
(
0 0
. .
0 0
0 8 M_
8
- -
A A
B C
- -
B A S E T
O
P
&
B
R
O
A
M
D
E
T
A
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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 L 0.170 0.270 Y D 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 E 9.000 BSC L A U G P V1 4.500 BSC . 2W 5 0 0.200 REF X 1.000 REF
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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 MFAX: RMFAX0@email.sps.mot.com - TOUCHTONE 602-244-6609 INTERNET: http://Design-NET.com
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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

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