High-Voltage Synchronous Buck Regulator Family

Micrel Inc. introduced the MIC28511/12/13, a family of pin-compatible high-voltage (HV) synchronous step-down switching regulators with integrated power switches capable of providing up to 4A (MIC28513) output current and a wide input supply range from 4.6V to 70V (MIC28512). The MIC28511/12/13 are offered in both Hyper Speed Control and HyperLight Load architectures, which allow for high V_IN (low V_OUT) operation and ultra-fast transient response while reducing the required output capacitance and providing very good light-load efficiency. These products can be used in wide variety applications including industrial control, power metering, telecom, and medical equipment. The MIC28511/12/13 is currently available in volume quantities with 1,000-quantity pricing starting at $1.49/$1.85/$1.42, respectively.

The MIC28511/12/13 feature adjustable output voltage as low as 0.8V with a guaranteed accuracy of 1 percent. A constant switching frequency can be programmed from 200kHz to 680kHz thereby allowing the customer increased flexibility in using a small inductor or operating at higher efficiency using lower switching frequency. The MIC28511/12/13 offers a full suite of protection features for reliable solutions under fault conditions, including under-voltage lockout to ensure proper operation under power sag conditions, internal soft start to reduce inrush current, fold-back current limit, “hiccup”-mode short-circuit protection, and thermal shutdown. The MIC28511/12/13 devices operate at -40°C to +125°C junction temperature range and are offered in very small 24-pin 3 mm x 4 mm FCQFN packages.