TRS3318E

• ESD Protection for RS-232 I/O Pins
  • ±15 kV (Human-Body Model)
  • ±8 kV (IEC 61000-4-2, Contact Discharge)
  • ±15 kV (IEC 61000-4-2, Air-Gap Discharge)
• 300-µA Operating Supply Current
• 1-µA Low-Power Standby Mode (With Receivers Active)
• Designed to Transmit at a Data Rate of
  460 kbps
• Auto-Powerdown Plus Option Features Flexible Power-Saving Mode
• Operates From a Single 2.25-V to 3-V V_CC Supply
• Designed to be Interchangeable With Industry Standard '3318 Devices

The TRS3318E is a dual-driver, dual-receiver, RS-232-compatible transceiver. The device features auto-powerdown plus and enhanced electrostatic discharge (ESD) protection integrated into the chip. Driver output and receiver input are protected to ±15 kV using the IEC 61000-4-2 Air-Gap Discharge method, ±8 kV using the IEC 61000-4-2 Contact Discharge method, and ±15 kV using the Human-Body Model (HBM).

The device operates at a data rate of 460 kbps. The transceiver has a proprietary low-dropout driver output stage, enabling RS-232-compatible operation from a 2.25-V to 3-V supply with a dual charge pump. The charge pump requires only four 0.1-µF capacitors and features a logic-level output (READY) that asserts when the charge pump is regulating and the device is ready to begin transmitting.

The TRS3318E achieves a 1-µA supply current using the auto-powerdown feature. This device automatically enters a low-power power-down mode when the RS-232 cable is disconnected or the drivers of the connected peripherals are inactive for more than 30 s. The device turns on again when it senses a valid transition at any driver or receiver input. Auto-powerdown saves power without changes to the existing BIOS or operating system.

This device is available in two space-saving packages: 20-pin SSOP and 20-pin TSSOP.