ST485A STMicroelectronics, ST485A Datasheet
ST485A
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ST485A Summary of contents
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... Current limiting and thermal shutdown for driver overload protection Latch-up free up to 500mA Description The ST485A is a low power, high speed transceiver for RS-485 and RS-422 communications. The device contains one driver and one receiver in half duplex configuration. The ST485A draws 3mA (typ.) of supply current when unloaded or fully loaded with disabled drivers ...
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... Contents Contents 1 Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1 Pin description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2 Truth tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3 Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 4 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 4.1 Logic input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 4.2 Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 4.3 Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4.4 Driver switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4.5 Receiver switching . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 5 Test circuit and typical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . 9 6 Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 7 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 2/19 ST485A ...
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... ST485A 1 Pin configuration Figure 1. Pin configuration 1.1 Pin description Table 1. Pin description Pin Symbol n° Receiver output. If A>B by 200mV, RO will be high; if A<B by 200mV, RO will low Receiver output enable enabled when RE is low high impedance 2 RE when RE is high high and DE is low, the device will enter a low power shutdown mode ...
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... L L Note Don’t care High impedance Table 3. Truth table (receiver) Inputs Note Don’t care High impedance 4/ Outputs A-B RO -0.2V H -0.2V L INPUTS OPEN H Outputs Mode Normal L Normal Z Normal Mode Normal Normal Normal ST485A ...
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... ST485A 3 Maximum ratings Table 4. Absolute maximum ratings Symbol V Supply voltage CC V Control input voltage (RE, DE Driver input voltage (DI Driver output voltage ( Receiver input voltage ( Receiver output voltage (RO) RO Note: Absolute maximum ratings are those values beyond which damage to the device may occur. ...
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... 100 -7V to 12V O Min Typ Max = Min Typ Max 0.8 2 2.0 1 -0.8 Min Typ Max 5 1 0.2 250 ST485A Unit Unit Unit ...
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... ST485A 4.3 Receiver (V = 4.5V to 5.5V referred 25° Table 8. Receiver electrical characteristics Symbol Parameter Receiver Differential Threshold V TH Voltage V Receiver Input Hysteresis TH V Receiver Output High Voltage OH V Receiver Output Low Voltage OL 3-State (High Impedance) Output I OZR Current at Receiver R Receiver Input Resistance ...
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... Typical values are A = 5V) (See Note Test conditions C = 15pF L = 15pF 15pF, S1 Closed 15pF, S2 Closed 15pF, S2 Closed 15pF, S1 Closed RL ST485A Min Typ Max Unit 0 ...
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... ST485A 5 Test circuit and typical characteristics Figure 2. Driver DC test load Figure 3. Receiver timing test load Figure 4. Driver/receiver timing test circuit Test circuit and typical characteristics 9/19 ...
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... Test circuit and typical characteristics Figure 5. Driver Timing Test Load Figure 6. Driver timing test load Figure 7. Driver enable and disable time 10/19 ST485A ...
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... ST485A Figure 8. Receiver propagation delay Figure 9. Receiver enable and disable time Test circuit and typical characteristics 11/19 ...
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... Test circuit and typical characteristics Figure 10. Receiver output current vs. output voltage (output low) Figure 12. Driver Diff. Output Voltage vs Common Mode Voltage (Diff. Output Low) 12/19 Figure 11. Receiver output current vs. output voltage (output high) Figure 13. Driver Diff. Output Voltage vs Common Mode Voltage (Diff. Output Low) ST485A ...
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... ST485A Figure 14. Driver Short Circuit Current vs Line Voltage (Output High) Figure 16. Receiver Input Current vs Input Voltage Test circuit and typical characteristics Figure 15. Driver Short Circuit Current vs. Line Voltage (Output Low) 13/19 ...
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... These packages have a Lead-free second level interconnect. The category of second level interconnect is marked on the package and on the inner box label, in compliance with JEDEC Standard JESD97. The maximum ratings related to soldering conditions are also marked on the inner box label. ECOPACK trademark. ECOPACK specifications are available at: 14/19 www.st.com ST485A ...
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... ST485A DIM. MIN 0.7 B 1. 0.44 Plastic DIP-8 MECHANICAL DATA mm. TYP MAX. 3.3 1.65 1.04 0.5 0.5 9.8 8.8 2.54 7.62 7.62 7.1 4.8 3.3 1.6 Package mechanical data inch MIN. TYP. MAX. 0.130 0.028 0.055 0.065 0.036 0.041 0.020 0.015 0.020 0.386 0.346 0.100 0.300 0.300 0.280 0.189 0.130 0.017 ...
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... DIM. MIN. A 1.35 A1 0.10 A2 1.10 B 0.33 C 0.19 D 4. 5.80 h 0.25 L 0.40 k ddd 16/19 SO-8 MECHANICAL DATA mm. TYP MAX. 1.75 0.25 1.65 0.51 0.25 5.00 4.00 1.27 6.20 0.50 1.27 ˚ (max.) 8 0.1 inch MIN. TYP. MAX. 0.053 0.069 0.04 0.010 0.043 0.065 0.013 0.020 0.007 0.010 0.189 0.197 0.150 0.157 0.050 0.228 0.244 0.010 0.020 0.016 0.050 0016023/C ST485A 0.04 ...
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... ST485A DIM. MIN 12 8.1 Bo 5.5 Ko 2.1 Po 3.9 P 7.9 Tape & Reel SO-8 MECHANICAL DATA mm. TYP MAX. 330 13.2 22.4 8.5 5.9 2.3 4.1 8.1 Package mechanical data inch MIN. TYP. MAX. 12.992 0.504 0.519 0.795 2.362 0.882 0.319 0.335 0.216 0.232 0.082 0.090 0.153 0.161 0.311 0.319 17/19 ...
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... Revision history 7 Revision history Table 11. Revision history Date Revision 28-Mar-2006 2 18/19 Order codes has been updated and new template. Changes ST485A ...
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... ST485A Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. ...