The MAX3320 is a combination of a microprocessor (µP) supervisory circuit and an RS-232 transceiver. It can precisely monitor 5V and 3.3V power supply voltages, and has a 100ms (minimum) power-on reset pulse width, power-supply transient immunity, and guaranteed RESET valid voltage down to VCC = 1V. The device also features 4µA supply current, always-active receivers, always-active power-on reset, and 4µA low-power shutdown, and can run at a guaranteed data rate of 250kbps.
The MAX3320 family combines a microprocessor supervisory circuit with an RS‑232 transceiver. It features a power‑on reset that stays asserted for at least 100 ms after VCC rises above the reset threshold, an active‑low RESET output, and a proprietary low‑dropout transmitter stage that operates from a 3 V to 5.5 V supply.
The device uses a dual charge‑pump architecture requiring four 0.1 µF external capacitors and is offered in a 20‑pin SSOP package. It supports multiple reset‑threshold options (A, B, L, T) and provides up to 250 kbps data rate with low 4 µA shutdown current.
| Data Rate | up to 250 kbps |
|---|---|
| Supply Voltage Range | 3 V to 5.5 V |
| Package | 20‑pin SSOP |
| AutoShutdown Plus Supply Current | 4 µA |
| External Charge‑Pump Capacitors | four 0.1 µF capacitors |
| Reset Threshold Options | A: 4.25 V, B: 2.85 V, L: 4.63 V, T: 3.08 V |
The MAX3320 can operate at data rates up to 250 kbps.
It works with a supply voltage from 3 V to 5.5 V.
Four 0.1 µF external capacitors are required.
RESET is active‑low and stays asserted for at least 100 ms after VCC rises above the reset threshold; it becomes open‑circuit when VCC falls below 1 V.