The MAX3224–MAX3227/MAX3244/MAX3245 are 3V-powered EIA/TIA-232 and V.28/V.24 communications interfaces with automatic shutdown/wakeup features and high data-rate capabilities. All devices achieve a 1µA supply current using Maxim’s revolutionary AutoShutdown Plus™ feature. These devices automatically enter a low-power shutdown mode when the RS-232 cable is disconnected or the transmitters of the connected peripherals are inactive, and the UART driving the transmitter inputs is inactive for more than 30 seconds. They turn on again when they sense a valid transition at any transmitter or receiver input. AutoShutdown Plus saves power without changes to the existing BIOS or operating system. The MAX3225/MAX3227/MAX3245 also feature MegaBaud™ operation, guaranteeing 1Mbps for high-speed applications such as communicating with ISDN modems. The MAX3224/MAX3226/MAX3244 guarantee 250kbps operation. The transceivers have a proprietary low-dropout transmitter output stage enabling true RS-232 per
The MAX3224‑MAX3227 and MAX3244‑MAX3245 are 3 V‑powered RS‑232 transceivers with AutoShutdown Plus and MegaBaud™ features. They operate from a 3.0 V to 5.5 V supply and provide low‑power operation (≈1 µA supply current) while supporting data rates up to 1 Mbps for the high‑speed devices.
The devices are offered in space‑saving TQFN, TSSOP and SSOP packages, with ordering information, absolute maximum ratings, electrical and timing characteristics, and pin descriptions provided for designers. Applications include notebook computers, cellular phones, battery‑powered handheld equipment, and printers.
| Supply Current (ForceOn) | ≈1 µA |
|---|---|
| Maximum Data Rate (MAX3224/3226/3244) | 250 kbps |
| Maximum Data Rate (MAX3225/3227/3245) | 1 Mbps |
| Operating Temperature Range (RoHS packages) | −40 °C to +85 °C |
| Package Types | TQFN, TSSOP, SSOP |
| Charge‑Pump Capacitors Required | Four 0.1 µF capacitors |
AutoShutdown Plus puts the transceiver into a low‑power shutdown mode when the RS‑232 cable is disconnected or all inputs are idle for more than 30 seconds, and it wakes the device when a valid transition is detected.
The MAX3224 supports a maximum data rate of 250 kbps.
Four 0.1 µF capacitors are required for the charge‑pump operation.
They are offered in TQFN, TSSOP, and SSOP packages.