Legacy Device: Motorola MC145583

The ML145583 is a CMOS transceiver composed of three drivers and five receivers that fulfills the electrical specifications of EIA–232–E, EIA–562, and CCITT V.28 while operating from a single + 3.3 or + 5.0 V power supply. This transceiver is a high–performance, low–power consumption device that is equipped with a standby function.
A voltage tripler and inverter converts the + 3.3 V to ± 8.8 V, or a voltage doubler and inverter converts the + 5.0 V to ± 8.8 V. This is accomplished through an on–chip 40 kHz oscillator and five inexpensive external capacitors.

FEATURES
Drivers:
• ± 5 V Minimum Output Swing at 3.3 or 5.0 V Power Supply
• 300 Ω Power–Off Impedance
• Output Current Limiting
• Three–State Outputs During Standby Mode

Receivers:
• ± 25 V Input Range
• 3 to 7 kΩ Input Impedance
• 0.8 V Hysteresis for Enhanced Noise Immunity
• Three–State Outputs During Standby Mode

Ring Monitor Circuit:
• Invert the Input Level on Rx1 to Logic Output Level on RIMON at Standby Mode