LTC4300A-2CMS8

LTC4300A-2CMS8 is a dual-channel hot-swap and I2C/SMBus bus protection device from Analog Devices (formerly Linear Technology). It provides two independent, current-limited high-side switches to power I2C devices, enabling safe hot-plugging, controlled power-up/down, and basic fault monitoring on an I2C bus. The “A” denotes automotive/extended temperature capability, and “CMS8” identifies the 8‑pin CMS/MSOP package.
Key features (typical):
- Two independent high-side switches with current limit and ramp control
- Fault/status reporting for each channel
- Suitable for hot-swap/board protection of I2C/SMBus devices
- Automotive-grade temperature range (-40°C to +125°C) on the A variant
- Compact 8-pin CMS8 package
Typical use:
- Powering and protecting I2C sensors, memories, or buffers on hot-pluggable boards
- Providing controlled inrush and fault isolation on dual I2C channels
For exact pinout, electrical specs, and application notes, refer to the LTC4300A data sheet.

Direct pin-for-pin equivalents do not exist. LTC4300A-2CMS8 is a dual I2C-bus switch/isolation device with hot-swap and current-limit features. Closest functional substitutes (not pin-compatible) include:
- NXP PCA9517A (2-channel I2C buffer/level shifter)
- TI PCA9515A/PCA9517A (I2C bus buffers)
- TI TXS0102 (2-bit bidirectional I2C translator)
- Analog Devices ADuM1250/1251 (I2C isolators)
Refer to datasheets for exact electrical/functional compatibility.

LTC4300A-2CMS8 features (concise):
- Dual, I2C-controlled high-side load switches (two channels)
- Hot-swap protection with controlled turn-on and soft-start
- Independent programmable current limit per channel
- I2C interface to enable/disable channels and set limits
- Fault reporting and alert outputs (FAULT/ALERT)
- Protection: overcurrent, overvoltage, undervoltage, and thermal shutdown
- Fast fault response with protective behavior and current foldback
- 8-pin CMS8/MSOP package; suitable for compact designs with low quiescent current
Note: For exact electrical specs (voltage ranges, current limits, sleep modes), refer to the datasheet.

- Pin count: 8 pins (CMS8 package, MSOP8-type)
- Function: I2C-controlled hot-swap controller with inrush/current-limit protection for a high-side MOSFET, protecting a power rail during hot-plug events (with fault/status reporting).

- Manufacturer: Analog Devices, Inc. (ADI). The LTC4300A-2CMS8 is produced under the Analog Devices umbrella (the LTC line originated from Linear Technology, which ADI acquired in 2017).
- What kind of company: A global semiconductor company that designs and manufactures analog, mixed-signal, and DSP integrated circuits used across many industries.

Applications:
- Hot‑swap power switching with I2C bus isolation for multi‑rail boards.
- I2C/SMBus bus extension and isolation to remote sensors or long cables, preventing back‑powering.
- Safe power‑up/power‑down sequencing and fault protection for microcontrollers and peripherals.
- I2C protection in harsh environments (telecom, industrial, automotive) against transients, shorts and noise.
- Backplane, motherboard or multi‑board systems needing isolated I2C communication across supplies.

An 8-pin MSOP (Plastic Small-Outline) package — the CMS8 suffix denotes the MSOP-8 package.