Update: 01 October, 2023
The MAX1932 is a low-noise, high-voltage output analog integrated circuit used to bias avalanche photodiodes (APDs) in optical receivers. The chip uses a constant-frequency, pulse-width modulated (PWM) boost topology combined with a unique architecture that maintains regulation with an optional RC or LC post filter inside its feedback loop, achieving very low output ripple and noise. The MAX1932 also integrates a precision reference voltage and error amplifier to maintain 0.5% output voltage accuracy. The MAX1932 protects expensive APDs against adverse operating conditions while providing optimal bias. Traditional boost converters measure switch current for protection, whereas the MAX1932 integrates accurate high-side current limiting to protect APDs under avalanche conditions. A current-limit flag allows easy calibration of the APD operating point by indicating the precise point of avalanche breakdown. The MAX1932 control scheme prevents output overshoot and undershoot to provide safe APD operation without data loss. The output voltage can be accurately set with either external resistors, an internal 8-bit DAC, an external DAC, or other voltage source. Output span and offset are independently settable with external resistors. This optimizes the utilization of DAC resolution for applications that may require limited output voltage range, such as 4.5V to 15V, 4.5V to 45V, 20V to 60V, or 40V to 90V.
File format: PDF
Size: -
MD5 Checksum: AFDAF38CD887B069521CEBD71E008042
Publication date: 07 May, 2012
Downloads: -
PDF Link: MAXIM MAX1932 handbook PDF