北京盛源荣达电子科技有限公司 （非本站正式会员）

• V_L Pin for Compatibility With Mixed-Voltage Systems
  Down to 1.8 V on Logic Side
• Enhanced ESD Protection on RIN Inputs and DOUT Outputs
  • ±8 kV IEC 61000-4-2 Air-Gap Discharge
  • ±8 kV IEC 61000-4-2 Contact Discharge
  • ±15 kV Human-Body Model
• Low 300-µA Supply Current
• Specified 1000-kbps Data Rate
• Auto Powerdown Plus Feature
• APPLICATIONS
  • Hand-Held Equipment
  • PDAs
  • Cell Phones
  • Battery-Powered Equipment
  • Data Cables

DESCRIPTION/ORDERING INFORMATION

The TRS3253E is a three-driver and five-receiver RS-232 interface device, with split supply pins for mixed-signal operations. All RS-232 inputs and outputs are protected to ±8 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.

The charge pump requires only four small 0.1-µF capacitors for operation from a 3.3-V supply. The TRS3253E is capable of running at data rates up to 1000 kbps, while maintaining RS-232-compliant output levels.

The TRS3253E has a unique V_L pin that allows operation in mixed-logic voltage systems. Both driver in (DIN) and receiver out (ROUT) logic levels are pin programmable through the V_L pin. This eliminates the need for additional voltage level shifter while interfacing with low-voltage microcontroller or UARTs. The TRS3253E is available in a space-saving QFN package (4 mm × 4 mm RSM).

Auto-powerdown plus can be disabled when FORCEON and FORCEOFF are high. With auto-powerdown plus enabled, the device activates automatically when a valid signal is applied to any receiver or driver input. INVALID is high (valid data) if any receiver input voltage is greater than 2.7 V or less than –2.7 V, or has been between –0.3 V and 0.3 V for less than 30 µs. INVALID is low (invalid data) if all receiver input voltages are between –0.3 V and 0.3 V for more than 30 µs. Refer to  for receiver input levels.