September 24, 2014 – Linear Technology Korea (CEO Hong Sa-gwak, www.linear.com) announced the launch of the LTC2946, a high side or low side charge, power and energy monitor for DC power rails in the 0V ~ 100V range. The integrated ±0.4% accuracy 12-bit ADC and external precision time base (crystal or clock) realize measurement accuracy better than ±0.6% for current and charge, and provide ±1% accuracy for power and energy. An internal time base with ±5% accuracy can serve as an alternative when an external time base is not available. All digital readout results including minimum and maximum values of voltage, current and power are stored in registers accessible via the I2C/SMBus interface. When a measurement exceeds a configurable threshold, the alarm output sends a signal, mitigating the burden of polling the host with data. The LTC2946 provides access to all essential parameters for accurately evaluating and managing board-level energy consumption. Furthermore, the wide operating range of this product makes it ideal for monitoring board energy consumption in blade servers, telecommunications, solar and industrial equipment, and AMC (advanced mezzanine card).

The LTC2946 provides a range of 2.7V ~ 5V when directly powered, receives 4V ~ 100V through an internal linear regulator, and can be supplied with 100V or more through an internal shunt regulator. Among three GPIO (general purpose input/output) pins, two can select options for accumulator enable and alarm output. The internal ADC operates in either continuous scan mode or snapshot mode. In shutdown mode, device current consumption decreases from 900μA to 15μA.

The LTC2946 is available in two options. The LTC2946 I2C interface features separate SDA input and output pins for standard or optically isolated I2C. Meanwhile, the LTC2946-1 is equipped with an inverted SDA output to reverse the opto-isolator option setting. Complying with commercial, industrial, automotive and military temperature grades, the LTC2946 is available in 16-pin MSOP and 4mm x 3mm DFN packages. It is offered at $3.95 per unit based on 1,000 units. Device samples and evaluation circuit boards are available through Linear Technology offices located in respective regions or online. For more information, refer to www.linear.com/products/power_monitors.

Photo Caption: 0V ~ 100V Energy, Power, Charge and Voltage Monitor with I2C/SMBus

Product Features: LTC2946

• Power supply voltage, current, charge, power & energy usage monitoring

• 0V ~ 100V monitoring range, 100V or above when shunt regulator is integrated

• 12-bit ADC with scan & snapshot modes

• I2C/SMBus digital interface

• Accuracy guaranteed:

o ±0.4% for 12-bit voltage

o ±0.6% for 12-bit current & 32-bit charge

o ±1% for 24-bit power & 32-bit energy

• Internal ±5%, external or crystal time base

• Minimum & maximum value logging

• Bias power supply range: 4V ~ 100V, or 2.7V ~ 5.9V

• Alarm when alert threshold is exceeded

• Split SDA easing opto-isolation

• Shutdown mode with IQ < 40μA

• 16-pin MSOP & 4mm x 3mm DFN packages