MAX5053

V_IN to GND ...........................................................-0.3V to +30V
V_CC to GND...........................................................-0.3V to +13V
FB, COMP, UVLO, CS to GND ..................................-0.3V to +6V
NDRV to GND..............................................-0.3V to (V_CC + 0.3V)
Continuous Power Dissipation (T_A = +70)
8-Pin MAX (derate 4.5mW/ above +70) ..................362mW
Operating Temperature Range ............................-40 to +85
Storage Temperature Range .............................-65 to +150
Junction Temperature......................................................+150
Lead Temperature (soldering, 10s) .................................+300
Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.

The MAX5052/MAX5053 current-mode PWM controllers contain all the control circuitry required for the design of wide-input-voltage isolated and nonisolated power supplies. The MAX5052 is well suited for universal input (rectified 85VAC to 265VAC) or telecom (-36VDC to -72VDC) power supplies. The MAX5053 is well suited for low-input-voltage (10.8VDC to 24VDC) power supplies.

The MAX5052/MAX5053 contain an internal error amplifier that regulates the tertiary winding output voltage.

This implements a primary-side regulated, isolated power supply, eliminating the need for an optocoupler.

An input undervoltage lockout (UVLO) is provided for programming the input-supply start voltage and to ensure proper operation during brownout conditions.

The input-supply start voltage of MAX5053 is externally programmable with a voltage-divider. To shutdown the MAX5053, the UVLO pin is pulled low. Internal digital soft-start reduces output voltage overshoot. The internal thermal shutdown circuit protects the device in the event the junction temperature exceeds +130.

The MAX5052 has an internal bootstrap UVLO with large hysteresis that requires a minimum voltage of 23.6V for startup. The MAX5053 does not have the internal bootstrap UVLO and can be biased directly from a minimum voltage of 10.8V.

The 262kHz switching frequency is internally trimmed to ±12% accuracy; this allows the optimization of the magnetic and filter components resulting in compact, cost-effective power supplies. The MAX5052A/ MAX5053A are offered with a 50% maximum duty-cycle limit. The MAX5052B/MAX5053B are offered with a 75% maximum duty-cycle limit. These devices are available in 8-pin MAX packages and operate over the -40 to +85 temperature range.