LT1976 - High Voltage 1.5A, 200kHz Step-Down Switching Regulator with 100μA Quiescent Current

LT1976 - High Voltage 1.5A, 200kHz Step-Down Switching Regulator with 100μA Quiescent Current - Linear Technology（凌力尔特）

The LT1976 is a 200kHz monolithic buck switching regulator that accepts input voltages up to 60V. A high efficiency 1.5A, 0.2 Ohm switch is included on the die along with all the necessary oscillator, control and logic circuitry. Current mode topology is used for fast transient response and good loop stability.

Innovative design techniques along with a new high voltage process achieve high efficiency over a wide input range. Efficiency is maintained over a wide output current range by employing Burst Mode operation at low currents, utilizing the output to bias the internal circuitry, and by using a supply boost capacitor to fully saturate the power switch. Patented circuitry maintains peak switch current over the full duty cycle range.* Shutdown reduces input supply current to less than 1μA. External synchronization can be implemented by driving the SYNC pin with logic-level inputs. A single capacitor from the CSS pin to the output provides a controlled output voltage ramp (soft-start). The device also has a power good flag with a programmable threshold and time-out and thermal shutdown protection.

The LT1976 is available in a 16-pin TSSOP package with Exposed Pad leadframe for low thermal resistance. The LT1977, a 500kHz increased switch frequency version of the LT1976, is also available. See the Applications Information section for selection criteria between the LT1976 and LT1977.

*Protected by U.S. Patents, including 6,498,466
**See Burst Mode Operation section for conditions