ST1480US Datasheet 3.3 V powered, 15 kV ESD protected, up to 12 Mbps true RS-485/RS-422 transceiver Features ESD protection 15 kV human body model 8 kV IEC 1000-4-2 contact discharge Operates from a single 3.3 V supply - no charge pump required SO8 Interoperable with 5 V logic 1 A low current shutdown mode max. Guaranteed 12 Mbps data rate -7 to 12 common mode input voltage range Half duplex versions available Industry standard 75176 pinout Current limiting and thermal shutdown for driver overload protection Guaranteed high receiver output state for floating, shorted or terminated inputs with no signal present Allows up to 64 transceivers on the bus Description The ST1480US is 15 kV ESD protected, 3.3 V low power transceiver for RS-485 and RS-422 communications. The device contains one driver and one receiver in half duplex configuration. The ST1480US transmits and receives at a guaranteed data rate of at least 12 Mbps. All transmitter outputs and receiver inputs are protected Product status link to 15 kV using human body model. Driver is short-circuit current limited and is ST1480US protected against excessive power dissipation by thermal shutdown circuitry that places the driver outputs into a high-impedance state. The ST1480US input has a true fail-safe feature that guarantees a logic high output if both inputs are open circuit, shorted together or in the presence of a termination with no signal on the bus. DS13697 - Rev 1 - April 2021 www.st.com For further information contact your local STMicroelectronics sales office.ST1480US Pin configuration 1 Pin configuration Figure 1. Pin connections Table 1. Pin description Pin Symbol Name and function 1 RO Receiver output. If A>B by 200 mV, RO is high if A< B by 200 mV, RO is low. Receiver output enable. RO is enabled when RE is low RO is high impedance when RE is high. If RE is high 2 RE and DE is low, the device enters a low power shutdown mode. Driver output enable. The driver outputs are enabled by bringing DE high. They are high impedance when DE 3 DE is low. If RE is high DE is low, the device enters a low-power shutdown mode. If the driver outputs are enabled, the part functions as line driver, while they are high impedance, it functions as line receivers if RE is low. Driver input. A low on DI forces output A low and output B high. Similarly, a high on DI forces output A high and 4 DI output B low. 5 GND Ground 6 A Non-inverting receiver input and non-inverting driver output. 7 B Inverting receiver input and inverting driver output. 8 VCC Supply voltage: VCC=3 V to 3.6 V. DS13697 - Rev 1 page 2/21