ST3243EB ST3243EC 15 kV ESD protected 3 to 5.5 V, 400 kbps, RS-232 transceiver with auto power-down Features ESD protection for RS-232 I/O pins: 8 kV IEC 1000-4-2 contact discharge 15 kV human body model 1 A supply current achieved when in auto power-down 250 kbps minimum guaranteed data rate Guaranteed 6 V/ms slew rate range TSSOP Guaranteed mouse drive ability 0.1 F external capacitors Meet EIA/TIA-232 specifications down to 3 V Available in TSSOP28 package The auto power-down feature functions when FORCEON is low and FORCEOFF is high. During Description this mode of operation, if the device does not sense a valid RS-232 signal, the driver outputs The ST3243E device consists of 3 drivers, 5 are disabled. If FORCEOFF is set low, both receivers and a dual charge-pump circuit. The drivers and receivers (expert R2B) are shut off, device meets the requirements of EIA/TIA and and supply current is reduced to 1 A. V.28/V.24 communication standards providing Disconnecting the serial port or turning off the high data rate capability and enhanced peripheral drives causes the auto power-down electrostatic discharge (ESD) protection. All condition to occur. transmitter outputs and receiver input are protected to 8 kV USING IEC 1000-4-2 contact Auto power-down can be disabled when discharge and 15 kV using the human body FORCEON and FORCEOFF are high, and should model. The receiver R2 is always active to be done when driving a serial mouse. With auto implement a wake-up feature for serial port. power-down enabled, the device is activated automatically when a valid signal is applied to any The ST3243E has a proprietary low-dropout receiver input. transmitter output stage enabling true RS-232 performance from a 3.0 V to 5.5 V supply with a Typical application are in notebook, subnotebook, dual charge pump. The device is guaranteed to palmtop computers, battery-powered equipment, run at data rates of 250 kbps while maintaining handheld equipment, peripherals and printers. RS-232 output levels. Table 1. Device summary Order codes Temperature range Package Packaging ST3243ECTR-E 0 to 70 C TSSOP28 (tape and reel) 2500 parts per reel ST3243EBTR - 40 to 85 C TSSOP28 (tape and reel) 2500 parts per reel October 2009 Doc ID 8648 Rev 12 1/16 www.st.com 16Contents ST3243EB, ST3243EC Contents 1 Pin configuration 3 2 Truth tables 5 3 Maximum ratings . 6 4 Electrical characteristics . 7 5 Application circuits 10 6 Timing diagrams . 11 7 Package mechanical data 12 8 Revision history . 15 2/16 Doc ID 8648 Rev 12