Peak temperature in high-power chips

System-level thermal transient analysis of High-Power Dynamic Microelectronics System is performed using numerical simulations. The SmartMOS-type device is packaged in 20 lead SOIC module with exposed copper slug. The package is attached to 4-layer PCB with embedded thermal vias. The challenge resides in the transient thermal interaction between the dynamic heat sources (high/low side motors), activated simultaneously at different powering profiles. Several operating steps are simulated, and the transient thermal behavior for each source is analyzed then optimized during the process. The low side motor reaches a peak temperature of ∼126.1°C at 2.25s, while the final temperature reached by the motor after one cycle (2.565 s) is ∼75.9°C. The DC current limit study indicates that the current over 1A exceeds the thermal budget. The case with 0.5A current limit reaches 135°C after 4 cycles, satisfying the thermal budget. Additional studies for an equivalent system were performed with only the high side driver actively dissipating 120W for 2.56 ms. The peak temperature reached by the system during the first cycle (2.56 us) is ∼65°C. Analytical study was performed to evaluate the steady state (final) temperature after a large number of dynamic powering cycles, based on heating/cooling behavior and superposition principle. The peak temperature reached by the IC will not exceed 92°C (using the steady state value and the temperature fluctuations per transient cycle). A correlation to predict the peak temperatures reached by the dynamic system after a long number of powering cycles is provided.

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1247Similar rate of thermal esophageal lesions are found in patients alternatively assigned to high power short duration (70W, 8s) vs. lesion index guided (35W) ablation for atrial fibrillation

EP Europace ◽

10.1093/europace/euaa162.361 ◽

2020 ◽

Vol 22 (Supplement_1) ◽

Author(s):

M Brunelli ◽

W Opara ◽

M Schwaar ◽

N John ◽

C Isensee ◽

...

Keyword(s):

Atrial Fibrillation ◽

Short Duration ◽

High Power ◽

Posterior Wall ◽

Similar Rate ◽

Temperature Monitoring ◽

Peak Temperature ◽

Self Healing ◽

Safe Alternative ◽

Thermal Lesions

Abstract Background wide antral pulmonary vein (PV) catheter ablation (CA) in patients with atrial fibrillation (AF) is safe and effective when permanent trans-mural lesions are achieved without causing harm to surrounding anatomical structures. Atrio-esophageal fistula, due to its high mortality, is the most dreadful complication related to CA for AF, therefore alternative radiofrequency (RF) approaches to reduce or eliminate this complication are currently studied. The shallower but wider lesions of high power short duration (HPSD) ablation might represent a safe alternative. Purpose to compare the rate of thermal esophageal lesions in patients with paroxysmal and persistent AF undergoing CA assigned to the 2 different RF modality. Methods one-hundred patients with paroxysmal and 100 with persistent AF will be alternatively assigned to undergo CA with the FlexAbility™ (HPSD group: 70W, 41°, 8 seconds) or the TactiCath™ (LSI-group: 35W, 41°, LSI: 5-5.5 posterior wall, up to 6 anywhere else) catheter. A 3-D mapping system, a steerable sheath and adenosine-test (30mg) were used in all patients. Posterior wall (PW) isolation in addition to PV isolation was performed in all, and patients with persistent AF were additionally treated with mitral and cavotricuspid isthmus ablation. Insertion of an esophageal probe was always attempted, and all patients underwent upper endoscopy 24 to 48 hours after CA. Results between June and October 2019, 71 patients (68 ± 10 years old, 32 (45%) female, 44 (60%) paroxysmal AF, AF duration 58 ± 81 months) were alternatively assigned to HPSD (36, 51%) or LSI-guided (35, 49%) ablation. No differences in clinical characteristics were found between groups. After 45 ± 18min and 30 ± 14 min of procedural and RF time, all PVs were isolated, and all spontaneous and adenosine-induced reconnections treated. Successful PW isolation was achieved with an additional 8 ± 3 and 7 ± 3 min of procedural and RF time. When HPSD and LSI-guided groups are compared, a similar rate of clinically non-relevant and self-healing thermal lesions at endoscopy was found (10, 27.8% vs. 10, 28.6%). Independent of the treatment group, a higher peak temperature identified patients with esophageal lesions (43.2° vs. 42°; P=.0065). A peak temperature value of 43.1° best identify patients most likely to develop thermal lesions (AUC 0.71, SE 84%, SP 39%). Interestingly, none of the 11 patients in whom esophageal probe insertion was not possible or attempted developed thermal lesions in comparison to 20 (33%) patients who underwent esophageal temperature monitoring (P=.0046). Conclusions: no difference in thermal induced esophageal lesions were found when the two different RF approach (HPSD vs. LSI guided) were compared. Interestingly, lack of temperature monitoring with an esophageal probe is associated with no thermal lesions at endoscopy.

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Dynamic Modeling and Wear-Based Remaining Useful Life Prediction of High Power Clutch Systems

Tribology Transactions ◽

10.1080/05698190590927451 ◽

2005 ◽

Vol 48 (2) ◽

pp. 208-217 ◽

Cited By ~ 32

Author(s):

Matthew Watson ◽

Carl Byington ◽

Douglas Edwards ◽

Sanket Amin

Keyword(s):

Dynamic Modeling ◽

High Power ◽

Life Prediction ◽

Remaining Useful Life ◽

Useful Life

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Less Power, Greater Conflict

Social Psychology ◽

10.1027/1864-9335/a000327 ◽

2018 ◽

Vol 49 (1) ◽

pp. 47-62 ◽

Cited By ~ 1

Author(s):

Petra C. Schmid

Keyword(s):

Low Power ◽

High Power ◽

Goal Pursuit ◽

Goal Conflict ◽

Personal Goals ◽

Multiple Goals ◽

Objective Performance ◽

The Future ◽

The Way

Abstract. Power facilitates goal pursuit, but how does power affect the way people respond to conflict between their multiple goals? Our results showed that higher trait power was associated with reduced experience of conflict in scenarios describing multiple goals (Study 1) and between personal goals (Study 2). Moreover, manipulated low power increased individuals’ experience of goal conflict relative to high power and a control condition (Studies 3 and 4), with the consequence that they planned to invest less into the pursuit of their goals in the future. With its focus on multiple goals and individuals’ experiences during goal pursuit rather than objective performance, the present research uses new angles to examine power effects on goal pursuit.

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