BEGIN:VCALENDAR VERSION:2.0 PRODID:IEEE vTools.Events//EN CALSCALE:GREGORIAN BEGIN:VTIMEZONE TZID:America/Los_Angeles BEGIN:DAYLIGHT DTSTART:20250309T030000 TZOFFSETFROM:-0800 TZOFFSETTO:-0700 RRULE:FREQ=YEARLY;BYDAY=2SU;BYMONTH=3 TZNAME:PDT END:DAYLIGHT BEGIN:STANDARD DTSTART:20241103T010000 TZOFFSETFROM:-0700 TZOFFSETTO:-0800 RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=11 TZNAME:PST END:STANDARD END:VTIMEZONE BEGIN:VEVENT DTSTAMP:20241108T015541Z UID:F8B72C0E-4AB4-4CCB-9881-5AA12B462000 DTSTART;TZID=America/Los_Angeles:20241107T160000 DTEND;TZID=America/Los_Angeles:20241107T173000 DESCRIPTION:ABSTRACT\nThe first vacuum tube amplifiers appeared circa 1912 and were used originally as audio amplifiers. Shortly thereafter they help ed to popularize AM radio broadcasting. Generating sufficient broadcast po wer was difficult and electricity costs were high for operators\, driving many key innovations to improve output power and efficiency\, particularly when amplifying signals with large peak-to-average power ratios. The Dohe rty Power Amplifier (D(oherty)PA)\, invented in 1936 by William Doherty wa s a transformative invention that enabled high power and efficiency simult aneously\, using two amplifiers in a configuration that enabled load modul ation to improve efficiency at output power backoff. It is surprising that after almost 90 years\, and a transformation from vacuum tubes to solid-s tate electronics\, that the D(oherty)PA remains one of the most popular PA architectures\, especially for mmWave PAs. In this talk\, I will review t he D(oherty)PA and several key innovations in PAs over the past century\, including outphasing (Chireix 1935)\, envelope elimination and restoration (Kahn 1952) and class-G/multi-supply (Feldman 1976)\, while providing sev eral examples of recent transformations to allow these PA innovations to o perate in modern transistor processes. The drive for innovations in PAs co ntinues today and I will then introduce the Digital PA\, a revolutionary t ransformation to the PA that embeds a DAC and mixer into a switching PA. T he D(igital)PA provides a pathway for high levels of integration that are necessary for multi- band and MIMO transmitters. It also provides a means to realize the voltage-mode D(oherty)PA\, linking the D(oherty)PA to the D (igital)PA.\n\nSpeaker(s): Dr. Jeffrey Walling\n\nAgenda: \nDATE/TIME\nThu rsday\, November 7\, 2024 at 4:00-5:30pm PDT\n\nLOCATION\nQualcomm Q Audit orium (6455 Lusk Blvd\, San Diego\, CA 92121)\nIn Person only\n*Non-Qualco mm Employees*: Please arrive 10-15 minutes earlier to find parking.\n\nBld g: Qualcomm Q Auditorium\, 6455 Lusk Blvd\, San Diego\, California\, Unite d States\, 92130 LOCATION:Bldg: Qualcomm Q Auditorium\, 6455 Lusk Blvd\, San Diego\, Califor nia\, United States\, 92130 ORGANIZER:jfshi@ieee.org SEQUENCE:9 SUMMARY:Over A Century of Electronic Power Amplifiers from D(oherty)PAs to D(igital)PAs URL;VALUE=URI:https://events.vtools.ieee.org/m/442810 X-ALT-DESC:Description: <br /><div>ABSTRACT</div>\n<div>The first vacuum tu be amplifiers appeared circa 1912 and were used originally as audio amplif iers. Shortly thereafter they helped to popularize AM radio broadcasting. Generating sufficient broadcast power was difficult and electricity costs were high for operators\, driving many key innovations to improve output p ower and efficiency\, particularly when amplifying signals with large peak -to-average power ratios. The Doherty Power Amplifier (D(oherty)PA)\, inve nted in 1936 by William Doherty was a transformative invention that enable d high power and efficiency simultaneously\, using two amplifiers in a con figuration that enabled load modulation to improve efficiency at output po wer backoff. It is surprising that after almost 90 years\, and a transform ation from vacuum tubes to solid-state electronics\, that the D(oherty)PA remains one of the most popular PA architectures\, especially for mmWave P As. In this talk\, I will review the D(oherty)PA and several key innovatio ns in PAs over the past century\, including outphasing (Chireix 1935)\, en velope elimination and restoration (Kahn 1952) and class-G/multi-supply (F eldman 1976)\, while providing several examples of recent transformations to allow these PA innovations to operate in modern transistor processes. T he drive for innovations in PAs continues today and I will then introduce the Digital PA\, a revolutionary transformation to the PA that embeds a DA C and mixer into a switching PA. The D(igital)PA provides a pathway for hi gh levels of integration that are necessary for multi- band and MIMO trans mitters. It also provides a means to realize the voltage-mode D(oherty)PA\ , linking the D(oherty)PA to the D(igital)PA.</div><br /><br />Agenda: <br /><div>DATE/TIME</div>\n<div>Thursday\, November 7\, 2024 at 4:00-5:30pm PDT<br><br>LOCATION</div>\n<div>Qualcomm Q Auditorium (6455 Lusk Blvd\, Sa n Diego\, CA 92121)<br>In Person only<br>*Non-Qualcomm Employees*: Please arrive 10-15 minutes earlier to find parking.</div> END:VEVENT END:VCALENDAR