February 23, 2012 – Linear Technology Korea (CEO Hong Sa-kwak) announced the release of a power supply manager (product name: LTC2974) equipped with EEPROM for complete digital management of power supply systems with four or more power rails. The LTC2974 monitors positive or negative supplies using an I2C interface and the PMBus instruction set, enabling rapid troubleshooting and debugging during the power system design, development, production, and failure analysis processes.

Any supply can be sequenced and controlled using tracking or time-based events as long as it has a 'run' pin. The LTC2974's four channels simultaneously monitor voltage and current as well as external temperature, allowing users to compensate for MOSFET RDS(ON) or inductor DCR shifting. All LTC2974 supply functions consistently provide excellent accuracy, with an unadjusted total error of less than ±0.25%. Users can intuitively configure and view the LTC2974's registers, user settings, and fault logs using the powerful LTpowerPlay™ GUI. For applications requiring four or more supplies, the LTC2974 enables cascading using a 1-wire synchronization bus, allowing for the formation of fault dependencies among devices sharing the fault bus.

The LTC2974 can be used in a wide range of applications, including uninterruptible power supplies (UPS), automotive, medical, video, and networking applications. The LTC2974 supports the digital management of pure analog power systems by integrating key building blocks such as differential measurement and conditioning, high-resolution data converters, long-term data retention EEPROM, and precision references. The programmable watchdog timer supervises external microcontrollers, FPGAs, and ASICs. All four channels are fully equipped with dedicated monitoring, supervision, sequencing, margining, trimming, and fault protection functions. Black-box fault logging provides a method to diagnose failures by storing critical parameters in EEPROM. In the field, the LTC2974 automatically provides continuous monitoring and takes programmed actions in response to failures. The LTC2974 is also protected by an internal die temperature sensor. Through this high level of mixed-signal integration, the LTC2974 can be managed reliably and easily, even for the most complex power supply systems.

As Linear continues to expand its digital power supply manager product line, the LTC2974 belongs to its 8-channel counterpart, the LTC2978, and complements Linear's fully standalone DC/DC regulators, such as the 15A LTM4627 or the dual 8A LTM4628, which are available in a 15mm x 15mm µModµle® package.

The LTC2974 is RoHS compliant and available in a 64-pin 9mm x 9mm QFN package for commercial and industrial temperature ranges. A DC1856 demo system utilizing a DC1613 USB-PMBus controller demonstrates the LTC2974 operating four individual supplies; it is available for purchase at www.linear.com or through local sales offices. The LTC2974 starts at $8.85 per unit in 1,000-unit quantities. For more information, please visit www.linear.com/product/LTC2974 .

Photo Caption: Quad Digital Power Supply Manager for Voltage, Current, and Temperature Monitoring

Product Features: LTC2974
• I2C/SMBus serial interface
• PMBus compatible instruction set
• CRC-supported configured EEPROM
• Logging black box failures via internal EEPROM
• Differential input, 16-bit ΔΣ ADC with total unadjusted error of less than ±0.25%
• Four voltage servos use a 10-bit DAC with soft connect function to precisely regulate the supply voltage
• Monitoring 4 output voltages, 4 output currents, and 1 input voltage
• 4 external temperature sensors and internal die temperature monitoring
• 4-channel sequencer, time-based or tracking
• Programmable watchdog timer
• 4 UV/OV VOUT & 1 VIN Supervisor
• 4 Overcurrent/Undercurrent Supervisors
• Multichannel fault management support
• The LTC2974 can supply power in the range of 3.3V or 4.5V to 15V.
• 64-pin 9mm × 9mm QFN package