The MAX25208 is a versatile automotive 60V/70V 2.2MHz step-down controller with 7 μIQs and selectable bypass mode
The MAX25206/MAX25207/MAX25208 are automotive 2.2MHz synchronous step-down controller ICs with 7 μIQs. The IC's input voltage range is 3.5V to 60V (MAX25206/7) and 70V (MAX25208). They can operate at 99% (typ) duty cycle to exit state. These controllers are suitable for applications with medium to high power requirements that operate over a wide input voltage range, such as in automotive cold start or engine stop-start conditions. The MAX25207 has an optional bypass mode that allows 100% high-side switching until the buck function is required during automotive transients.
The MAX25206/MAX25207/MAX25208 step-down controllers operate at frequencies up to 2.2MHz to allow smaller external components, reduce output ripple, and guarantee no AM band interference. Adjustable switching frequency (220 kHz to 2200 kHz). Synchronization input programmability enables three frequency modes to optimize performance: forced fixed frequency operation, skip mode with ultra-low quiescent current, and synchronization to an external clock. The IC also provides a sync output, allowing two AD7890AN-10 controllers to operate in parallel. The MAX25206/MAX25207/MAX25208 feature a pin-selectable spread-spectrum option for frequency modulation to minimize EMI interference.
The MAX25206/MAX25207/MAX25208 have good monitor and undervoltage lockout features. Protection features include cycle-by-cycle current limit and thermal shutdown. These controllers are specified to operate over the -40°C to +125°C automotive temperature range.
Simplified block diagram
●Meet stringent OEM module power consumption and performance specifications
- Quiescent current in skip mode at 7μVOUT=3.3V
—±1.5% Output voltage accuracy: 5.0V/3.3V fixed, or 1V~10V adjustable
●Enable crank-ready design
— Wide input power supply range from 3.5V to 42V
EMI reduction feature reduces interference to sensitive radio frequency bands without sacrificing wider input voltage range
—50ns (typ) minimum turn-on time guaranteed at 2.2MHz, no jump operation at 3.3V car battery output
- spread spectrum option
—Frequency sync input
- Resistor programmable frequency between 220kHz and 2.2MHz
Integrated and thermally enhanced packaging saves board space and cost
—2.2MHz Buck Controller
—180° out-of-phase sync output
— Current-mode controller with forced continuous and skip modes
— Thermally enhanced 20-pin side wettable (SW) TQFN-EP package
●Protection function improves system reliability
- Power supply under voltage lockout
- Overheating and short circuit protection
— Output overvoltage and undervoltage monitoring
—-40°C to +125°C Grade 1 automotive temperature range
●24V truck system, infotainment system, 48V system.