ST485 STMICROELECTRONICS | Alldatasheet
Document overview
- Manufacturer or author: Provided By ALLDATASHEET.COM(FREE DATASHEET DOWNLOAD SITE)
- PDF pages: 19
Technical content
Datasheet sections
- 1 Pin configuration
- 1.1 Pin description
- 2 Truth tables
- 3 Maximum ratings
- 4 Electrical characteristics
- 4.1 Driver switching characteristics
- 4.2 Receiver switching characteristics
- 5 Test circuit and typical characteristics
- 6 Package mechanical data
- 7 Revision history
Part number Temperature range Package Comments ST485CN 0 to 70 °C DIP-8 50parts per tube / 40tube per box ST485BN -40 to 85 °C DIP-8 50parts per tube / 40tube per box ST485XN -55 to 125 °C DIP-8 50parts per tube / 40tube per box ST485CD 0 to 70 °C SO-8 (Tube) 100parts per tube / 20tube per box ST485BD -40 to 85 °C SO-8 (Tube) 100parts per tube / 20tube per box ST485CDR 0 to 70 °C SO-8 (Tape & reel) 2500 parts per reel ST485BDR -40 to 85 °C SO-8 (Tape & reel) 2500 parts per reel ST485XDR -55 to 125 °C SO-8 (Tape & reel) 2500 parts per reel ST485 Low power RS-485/RS-422 transceiver General features I Low quiescent current: 300mA I Designed for RS-485 interface application I -7V to 12V common mode input voltage range I Driver maintains high impedance in 3-state or with the power OFF I 70mV tipycal input hysteresis I 30ns propagation delay, 5ns skew I Operate from a single 5V supply I Current limiting and thermal shutdown for driver overload protection I Allows up to 64 transceivers on the bus
Description
The ST485 is al low power transceiver for RS-485 and RS-422 communication. Each part contains one driver and one receiver. This transceiver draw 300mA (typ.) of supply current when unloaded or fully loaded with disabled drivers. It operates from a single 5V supply. Driver is short-circuit current limited and is protected against excessive power dissipation by thermal shutdown circuitry that placed the driver outputs into a high-impedance state. The ST485 is designed for bi-directional data communications on multipoint bus transmission line (half-duplex applciations). The ST485 is available in three temperature range: commercial (0°C to 70°C), industrial (- 40°C to 850°C) and automotive (-55°C to 125°C) DIP-8 SO-8
1 Pin configuration
Figure 1. Pin configuration
1.1 Pin description
Table 1. Pin description
1 RO Receiver Output
2 RE Receiver Output Enable
3 DE Driver Output Enable
4 DI Driver Input
5 GND Ground
7 B Inverting Receiver Input and Inverting Driver Output
2 Truth tables
Table 2. Truth table (driver) Table 3. Truth table (receiver)
3 Maximum ratings
Note: Absolute maximum ratings are those values beyond which damage to the device may occur. magnitude of +7V, but their absolute addition can not exceed 13 V. Table 4. Absolute maximum ratings
4 Electrical characteristics
Table 5. DC Electrical characteristics
4.1 Driver switching characteristics
- All currents into device pins are positive; all cuttents out of device pins are negative; all voltages are referenced to devi ce
- Supply current specification is valid for loaded transmitters when V DE = 0V
- Applies to peak current. See typical Operating Characteristics.
Table 6. Driver switching characteristics
- All currents into device pins are positive; all cuttents out of device pins are negative; all voltages are referenced to devi ce
4.2 Receiver switching characteristics
Table 7. Receiver switching characteristics
- All currents into device pins are positive; all cuttents out of device pins are negative; all voltages are referenced to devi ce
5 Test circuit and typical characteristics
Figure 2. Driver DC test load Figure 3. Receiver timing test load Figure 4. Drive/receiver timing test circuit Figure 5. Driver timing test load
6 Package mechanical data
In order to meet environmental requirements, ST offers these devices in ECOPACK® packages. 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 is an ST trademark. ECOPACK specifications are available at: www.st.com
DIM. mm. inch A 3.3 0.130 a1 0.7 0.028 B 1.39 1.65 0.055 0.065 B1 0.91 1.04 0.036 0.041 b 0.5 0.020 b1 0.38 0.5 0.015 0.020 D 9.8 0.386 E 8.8 0.346 e 2.54 0.100 e3 7.62 0.300 e4 7.62 0.300 F 7.1 0.280 I 4.8 0.189 L 3.3 0.130 Z 0.44 1.6 0.017 0.063 Plastic DIP-8 MECHANICAL DATA P001F
DIM. mm. inch A 1.35 1.75 0.053 0.069 A1 0.10 0.25 0.04 0.010 A2 1.10 1.65 0.043 0.065 B 0.33 0.51 0.013 0.020 C 0.19 0.25 0.007 0.010 D 4.80 5.00 0.189 0.197 E 3.80 4.00 0.150 0.157 e 1.27 0.050 H 5.80 6.20 0.228 0.244 h 0.25 0.50 0.010 0.020 L 0.40 1.27 0.016 0.050 k ˚ (max.) ddd 0.1 0.04 SO-8 MECHANICAL DATA 0016023/C
DIM. mm. inch A 330 12.992 C 12.8 13.2 0.504 0.519 D 20.2 0.795 N 60 2.362 T 22.4 0.882 Ao 8.1 8.5 0.319 0.335 Bo 5.5 5.9 0.216 0.232 Ko 2.1 2.3 0.082 0.090 Po 3.9 4.1 0.153 0.161 P 7.9 8.1 0.311 0.319 Tape & Reel SO-8 MECHANICAL DATA
7 Revision history
Table 8. Revision history 21-Mar-2006 12 Order codes has been updated and new template.