• ESD Protection for RS-232 Bus Pins
  • ±15-kV Human-Body Model (HBM)
  • ±8-kV IEC61000-4-2, Contact Discharge
  • ±15-kV IEC61000-4-2, Air-Gap Discharge
• Meets or Exceeds the Requirements of TIA/EIA-232-F and ITU v.28 Standards
• Operates With 3-V to 5.5-V VCC Supply
• Operates up to 500 kbit/s
• Two Drivers and Two Receivers
• Low Standby Current . . . 1 µA Typ
• External Capacitors . . . 4 × 0.1 µF
• Accepts 5-V Logic Input With 3.3-V Supply
• Alternative High-Speed Pin-Compatible Device (1 Mbit/s) for TRS3222E
• APPLICATIONS
  • Battery-Powered Systems
  • PDAs
  • Notebooks
  • Laptops
  • Palmtop PCs
  • Hand-Held Equipment

DESCRIPTION/ORDERING INFORMATION

The TRS3222E consists of two line drivers, two line receivers, and a dual charge-pump circuit with ±15-kV ESD protection pin to pin (serial-port connection pins, including GND).

The device meets the requirements of TIA/EIA-232-F and provides the electrical interface between an asynchronous communication controller and the serial-port connector. The charge pump and four small external capacitors allow operation from a single 3-V to 5.5-V supply. The device operates at typical data signaling rates up to 500 kbit/s and a maximum of 30-V/µs driver output slew rate.

The TRS3222E can be placed in the power-down mode by setting the power-down (PWRDOWN) input low, which draws only 1 µA from the power supply. When the device is powered down, the receivers remain active while the drivers are placed in the high-impedance state. Also, during power down, the onboard charge pump is disabled; V+ is lowered to VCC, and V– is raised toward GND. Receiver outputs also can be placed in the high-impedance state by setting enable (EN) high.