= Mike Beckman
{c}
<Mike Beckman> is an <electrical engineer> identified in a 2013 <Texas Instruments> reference design as a systems engineer who, at that time, managed its converter product line. With <Luis Chioye>, he coauthored <Precision Thermocouple Measurement with the ADS1118 by Mike Beckman and Luis Chioye>, combining an <analog-to-digital converter>, <thermocouple> input and on-chip <temperature> sensor.<Precision Thermocouple Measurement with the ADS1118 by Mike Beckman and Luis Chioye>[Title page and §9, printed p. 23, authors and contemporary engineering roles]{ref}
Their design treats <cold-junction compensation> as both an electrical calculation and a thermal-layout problem. It places the converter near the connector and uses copper regions to improve <cold-junction thermal coupling>, while separating nearby heat sources. Its tests distinguish changing the reference-junction <temperature> from changing the measuring-junction <temperature>.<Precision Thermocouple Measurement with the ADS1118 by Mike Beckman and Luis Chioye>[§4, printed p. 15, Figure 11; §7, printed pp. 20–21]{ref}
A simple original linear model illustrates the reason. If a <thermocouple> has stipulated sensitivity $S=40\,\mathrm{\mu V/K}$ and measures $V=2\,\mathrm{mV}$, then $V=S(T_h-T_c)$ implies $T_h-T_c=50\,\mathrm K$. A reference junction at $25\,{}^{\circ}\mathrm C$ therefore gives $T_h=75\,{}^{\circ}\mathrm C$. Reading that junction as $30\,{}^{\circ}\mathrm C$ instead gives $80\,{}^{\circ}\mathrm C$, despite perfect measurement of $V$. The model uses constant sensitivity only for illustration; actual <cold-junction compensation> uses the appropriate thermoelectric conversion.
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