VR Module Current Sense Accuracy via Adaptive Temperature Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing power management algorithms for central processing units (CPUs) in information handling systems face challenges in achieving accurate temperature compensation, particularly due to nonlinear temperature coefficient relationships between current sensors and high side drivers, leading to inaccuracies in current sense measurements across varying temperature ranges.
Innovation Solution
The implementation of a temperature-compensated power control system within the voltage regulation (VR) module, which includes a current sensor and a temperature sensor integrated into the VR module's integrated circuit die, uses empirically-derived temperature coefficients to adjust monitored current values, thereby controlling voltage-regulated power and addressing nonlinear temperature coupling issues.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a temperature sensor is placed at one location on the integrated circuit die to measure temperature, then the temperature measurement is simpler and the device structure is less complex, but the temperature measurement accuracy deteriorates due to nonlinear temperature coefficient relationship with the high side driver
Solution Approach 1:
The patent applies parameter changes by using empirically-derived temperature coefficients that are stored in a lookup table. These coefficients are determined through empirical testing at different temperatures and currents, and the VR controller selects and applies the appropriate coefficient based on the current operating conditions. This transforms the fixed sensor location into a variable measurement system that compensates for position-related inaccuracies through parameter adjustment.
Solution Approach 2:
The patent implements feedback by continuously monitoring the temperature at the sensor location and using this information to adjust the current sense measurements through temperature coefficient compensation. The VR controller reads the temperature sensor output, retrieves the appropriate temperature coefficient from the lookup table, and applies compensation to the current sense readings. This closed-loop feedback mechanism corrects measurement errors caused by the nonlinear temperature coefficient relationship.
2Measurement precision
If empirically-derived temperature coefficients are used to compensate for nonlinear temperature effects, then the current sense measurement accuracy is improved across varying temperature ranges, but the device complexity increases due to additional lookup tables and compensation calculations
Solution Approach 1:
The patent applies preliminary action by pre-determining and storing temperature coefficients through empirical testing before the actual operation of the voltage regulator. The coefficients are calculated and stored in a lookup table during the manufacturing or calibration phase, covering a range of temperatures and current conditions. During operation, the VR controller simply retrieves the pre-calculated coefficient corresponding to the current temperature and applies it, avoiding the need for complex real-time calculations.
3Speed
If temperature compensation is implemented using a lookup table with empirically-derived coefficients, then the compensation speed is improved and real-time adjustment is achieved, but the memory requirements and data storage complexity increase
Solution Approach 1:
The patent applies partial action by implementing temperature compensation only at discrete temperature and current points rather than continuously across all possible values. The lookup table contains coefficients for specific operating conditions that were determined through empirical testing. The VR controller uses the temperature sensor reading to index into the lookup table and retrieve the appropriate coefficient, applying compensation only when needed based on the current operating point.
Data Source
AI summary
An information handling system (IHS) includes temperature-compensated power control by a voltage regulation (VR) module to: (i) receive a monitored current (Imon) value from a current sensor integrated into the VR module; (ii) receive a temperature value from the temperature sensor also integrated into the VR module; (iii) determine a temperature-compensated Imon value based at least in part on the Imon value, the temperature value, and an empirically-derived temperature coefficient defined at the Imon value and the temperature value; and (iv) control the voltage-regulated power at least in part based on the temperature-compensated Imon value. The empirically-derived temperature coefficient adjusts for nonlinear portions of temperature coupling relationship between a portion of an integrated circuit (IC) die that can include the current sensor and the temperature sensor and a temperature experienced by by active portion of VR module.