MAX253CSA+

MAX253CSA+ is a Maxim/Analog Devices RS-232 transceiver. It provides two TTL/CMOS-to-RS-232 drivers and two RS-232 receivers, enabling a microcontroller or logic device to talk to a PC-style serial port. The device generates the required RS-232 voltages from a single supply (typically 3.0–5.5 V) using an internal charge-pump, so no negative supply is needed. The “+CSA” suffix indicates a RoHS-compliant, lead-free version (exact packaging/temperature range varies—check the datasheet). Key points: external charge-pump capacitors are required; it supports standard RS-232 levels and data rates; designed for low quiescent current and simple interfacing to TTL/CMOS logic. Typical applications include microcontroller-to-PC serial links, embedded serial interfaces, modems, and other equipment requiring RS-232 connectivity. For exact specs (voltage swing, baud-rate support, pinout, and package), consult the MAX253CSA+ datasheet.

Equivalent products (2-channel RS-232 transceivers with charge-pump, 3–5.5V operation):
- TI SP3232 / SP3232E
- Analog Devices ADM232 / ADM232A
- STMicroelectronics ST3232
All are functionally similar to MAX253CSA+; for exact cross-reference, provide your desired supply voltage and package.

Key features of MAX253CSA+ (RS-232 transceiver):
- Dual RS-232 transmitter/receiver pair (2 drivers, 2 receivers)
- TTL/CMOS logic inputs; RS-232 level outputs and inputs
- On-chip charge pump to generate RS-232 voltages
- Requires only four external capacitors for the pump
- Single-supply operation (typical 3V–5.5V; 5V nominal)
- Low quiescent current and low overall power consumption
- Robust ESD protection on RS-232 lines
- Available in small packages (e.g., 8-pin SOIC/MSOP)
- RoHS-compliant; industrial/extended temp variants available (CSA+)
Note: Always check the latest datasheet for exact voltage ranges, cap values, and temp specifications for your specific package and revision.

- Pin count: 16 pins (SO-16/SSOP-16 package).
- Function: Dual RS-232 transceiver (two drivers and two receivers) that converts TTL/CMOS logic to RS-232 levels and RS-232 signals back to TTL/CMOS; uses an internal charge pump to generate RS-232 voltages from a single 3V–5.5V supply (external capacitors required for the pump).

- Manufacturer: Maxim Integrated (now part of Analog Devices, Inc.).
- What kind of company: A fabless semiconductor company that designs and markets analog and mixed-signal integrated circuits.

MAX253CSA+ is an RS-232 transceiver/level shifter (TTL/CMOS to RS-232) with an integrated charge pump. Typical application areas include:
- Serial interfaces for embedded systems and microcontrollers
- PCs, laptops, POS terminals, printers, modems
- Industrial automation, instrumentation, data loggers, test equipment
- Telecom and network equipment requiring RS-232 links
- Any device needing reliable RS-232 communication with low power and small footprint.

An 8-pin SOIC (surface-mount) package.