Page 192 - The Art and Science of Analog Circuit Design

Tripping the Light Fantastic

C1 = WIMA MKP-20
Q1,02 = ZETEX ZTX849 OR ROHM 2SC5001
L1 = COILTRON)CSCTX150-4
T1 = SUMIOAEPS-207
* = 1% FILM RESISTOR
00 NOT SUBSTITUTE COMPONENTS
COILTRONICS (305) 781-8900, SUMIDA (708) 956-0666

Figure 11-35.
The "low
thermometer"
circuit using a plifier's common mode range, and normal circuit operation commences.
micropower, preci- The result of all this is a 1.6% efficiency gain, permitting an overall cir-
sion topside sens- cuit efficiency of just below 92%.
ing amplifier.
Supply bootstrap-
ping eliminates Epilogue
input common
mode requirement,
Our understanding with Apple Computer gave them six months sole use
permitting a 1.6% of everything I learned while working with them. After that, we were
efficiency gain.
free to disclose the circuit and most attendant details to anyone else,
which we did. It found immediate use in other computers and applica-
tions, ranging from medical equipment to automobiles, gas pumps, retail
terminals and anywhere else LCD displays are used. The development
work consumed about 20 months, ending in August, 1993. Upon its
completion I immediately fell into a rut, certain I would never do any-
thing worthwhile again.

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