SBOS074E September 1997 – June 2018 ISO124
PRODUCTION DATA.
Refer to the PDF data sheet for device specific package drawings
An input amplifier (A1, as shown in Functional Block Diagram) integrates the difference between the input current (VIN/200 kΩ) and a switched ±100-µA current source. This current source is implemented by a switchable 200-µA source and a fixed 100-µA current sink. To understand the basic operation of the modulator, assume that VIN = 0 V. The integrator will ramp in one direction until the comparator threshold is exceeded. The comparator and sense amp will force the current source to switch; the resultant signal is a triangular waveform with a 50% duty cycle. The internal oscillator forces the current source to switch at 500 kHz. The resultant capacitor drive is a complementary duty-cycle modulation square wave