September 18, 2012 – Linear Technology Korea (CEO Hong Sa-gwak) announced the launch of the LTM2883, a 6-channel SPI/digital or I2C digital µModule® isolator with triple-rail regulated power suitable for 3.3V and 5V systems. In industrial applications, ground potential can vary widely, often exceeding tolerable ranges and interfering with communication or, in severe cases, damaging components. The LTM2883 blocks ground loops by electrically isolating communication signals, isolating logic-level interfaces at the internal inductive isolation barrier on each side, and withstands common-mode voltage ranges up to 2,500VRMS. The LTM2883's low-EMI isolated DC-DC converter supplies power to the communication interface and provides regulated power outputs of 5V, +12.5V, and -12.5V, making it ideal for powering data converters in data acquisition systems. Through 2,500VRMS galvanic isolation, with onboard secondary power and communication interface operation up to 20Mbps, the LTM2883 requires no external components and provides a simple µModule solution suitable for isolated data communication.

The LTM2883 is supplied in two communication interface versions. The LTM2883-I complies with I2C up to 400kHz via bidirectional serial data (SDA) and clock (SCL), plus three additional isolated CMOS signals operating up to 20Mbps. The LTM2883-S complies with SPI and provides all six CMOS digital isolator communication channels. All channels operate up to 20Mbps and include three forward signals (/CS, SCK, and SDI) and three reverse signals (SDO, DO1, and DO2). When configured for SPI communication, the maximum clock speed is 8MHz unidirectional or 4MHz bidirectional.

The onboard 2MHz DC-DC converter supplies power to the LTM2883, and three isolated power supply outputs can source up to 20mA across the entire operating temperature range. The logic supply pin provides direct interface capability with low-voltage microcontrollers scaling down to 1.62V, and the ON pin allows the LTM2883 to shut down using less than 10µA. Additional features include uninterrupted communication capability against common-mode transients of 30kV/µs or greater, and robust ±10kV ESD HBM protection for the isolation barrier.
The LTM2883 is available in 3.3V or 5V supply voltage versions. The LTM2883 is supplied in a 15mm x 11.25mm surface-mount BGA package, with all integrated circuits and passive components supplied in a RoHS-compliant μModule package. Pricing starts at $11.95 per unit in quantities of 1,000. Detailed information is available at www.linear.com/product/LTM2883.


Photo Caption: Isolated 4MHz SPI Interface

Product Features: LTM2883

• UL-rated 6-channel logic isolator: 2500VRMS
• UL File Number: #E151738
• Isolated regulated DC power:
o 3V to 5V at up to 30mA
o ±12.5V at up to 20mA
• No external components required
• High common-mode transient immunity: 30kV/µs
• High-speed operation:
o 10MHz digital isolation (LTM2883-S)
o 8MHz/4MHz SPI isolation (LTM2883-S)
o 400kHz I2C compliant isolation (LTM2883-I)
• 3.3V (LTM2883-3) or 5V (LTM2883-5) operation
• 1.62V to 5.5V logic supply for flexible digital interface
• ±10kV ESD HBM protection for isolation barrier
• 15mm x 11.25mm x 3.42mm BGA package