The MAX15004/MAX15005 high-performance, current-mode PWM controllers operate at an automotive input voltage range from 4.5V to 40V (load dump). The input voltage can go lower than 4.5V after startup if IN is bootstrapped to a boosted output voltage. The controllers integrate all the building blocks necessary for implementing fixed-frequency isolated/nonisolated power supplies. The general-purpose boost, flyback, forward, and SEPIC converters can be designed with ease around the MAX15004/MAX15005.
The current-mode control architecture offers excellent line-transient response and cycle-by-cycle current limit while simplifying the frequency compensation. Programmable slope compensation simplifies the design further. A fast 60ns current-limit response time, low 300mV current-limit threshold makes the controllers suitable for high-efficiency, high-frequency DC-DC converters. The devices include an internal error amplifier and 1% accurate reference to facilitate the primary-side regulated, single-ended flyback converter or nonisolated converters.
An external resistor and capacitor network programs the switching frequency from 15kHz to 500kHz (1MHz for the MAX15005). The MAX15004A/MAX15005 provide a SYNC input for synchronization to an external clock. The maximum FET-driver duty cycle for the MAX15004A/B/C/D is 50%. The maximum duty cycle can be set on the MAX15005A/B/C/D by selecting the right combination of RT and CT.
The input undervoltage lockout (ON/active-low OFF) programs the input-supply startup voltage and can be used to shutdown the converter to reduce the total shutdown current down to 10µA. Protection features include cycle-by-cycle and hiccup current limit, output overvoltage protection, and thermal shutdown.
The MAX15004/MAX15005 are available in space-saving 16-pin TSSOP and thermally enhanced 16-pin TSSOP-EP packages. All devices operate over the -40°C to +125°C automotive temperature range.
Applications
- Automotive
- Isolated Flyback, Forward, Nonisolated SEPIC, Boost Converters
- Vacuum Fluorescent Display (VFD) Power Supply
