Small Boost Converter with Current Monitor Is Ideal for APD-Biasing in Fiber Modules

Maxim Integrated Products introduces the MAX15031, a constant-frequency, pulse-width modulated (PWM) step-up converter that is designed for low-voltage systems that require a locally generated high voltage. Operating from a 2.7V to 11V supply, this device delivers a low-noise output voltage up to 76V (300mW of power) without an external voltage doubler. Additionally, Maxim's advanced BiCMOS process technology enables the MAX15031 to integrate a high-side current monitor with fast (1microsecond) current limiting to save space and cost in diode-biasing applications. This device is ideal for applications such as avalanche photodiode (APD) biasing, PIN biasing, and varacter biasing in fiber modules.

The MAX15031 utilizes peak current-mode PWM architecture with a fixed switching frequency of 400kHz, thus producing a low-noise output. The onboard current monitor offers three decades of dynamic range, and monitors current from 500nA to 4mA with high accuracy. Resistor-adjustable current limiting protects the APD from optical power transients. Internal soft-start circuitry limits the input inrush current during power-up, while a clamp diode protects the monitor's output from overvoltage conditions.

The MAX15031 is available in a space-saving, 4mm x 4mm, 16-pin TQFN package, and is fully specified over the -40°C to +125°C temperature range. Prices start at $1.65 (1000-up, FOB USA).