MAX15031

The MAX15031 consists of a constant-frequency pulsewidth modulating (PWM) step-up DC-DC converter with an internal switch and a high-side current monitor with high-speed adjustable current limiting. This device can generate output voltages up to 76V and provides current monitoring up to 4mA (up to 300mW). The device can be used for a wide variety of applications such as avalanche photodiode biasing, PIN biasing, or varactor biasing, and LCD displays. The MAX15031 operates from 2.7V to 11V.

Features of the MAX15031 are:(1)wide output-voltage range from (VIN + 1V) to 76V; (2)internal 1 (typ) 80V switch; (3)300mW boost converter output power; (4)accurate ±10% (500nA to 1mA) and ±3.5% (1mA to 4mA) high-side current monitor; (5)resistor-adjustable ultra-fast APD current limit (1s response time); (6)open-drain current-limit indicator flag; (7)400kHz fixed switching frequency; (8)constant PWM frequency provides easy filtering in low-noise applications; (9)internal soft-start; (10)2A (max) shutdown current.The constant-frequency (400kHz), current-mode PWM architecture provides low-noise output voltage that is easy to filter. A high-voltage, internal power switch allows this device to boost output voltages up to 76V.Internal soft-start circuitry limits the input current when the boost converter starts. The MAX15031 features a shutdown mode to save power.

The absolute maximum ratings of the MAX15031 can be summarized as:(1)PWR,IN to GND:-0.3V to +12V;(2)storage temperature range:-65 to +150;(3)junction temperature:150;(4)operating temperature range:-40 to 125;(5)LX to PGND:-0.3V to +80V;(6)continuous power dissipation:2000mW.Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.The MAX15031 operates in discontinuous mode in order to reduce the switching noise caused by reversevoltage recovery charge of the rectifier diode. Other continuous mode boost converters generate large voltage spikes at the output when the LX switch turns on because there is a conduction path between the output,diode, and switch to ground during the time needed for the diode to turn off and reverse its bias voltage.