LTC1878EMS8

Product Summary

The LTC1878EMS8 is a high efficiency monolithic synchronous buck regulator using a constant frequency, current mode architecture. Supply current during operation is only 10mA and drops to < 1mA in shutdown. The 2.65V to 6V input voltage range makes the LTC1878EMS8 ideally suited for single Li-Ion battery-powered applications. 100% duty cycle provides low dropout operation, extending battery life in portable systems. Switching frequency is internally set at 550kHz, allowing the use of small surface mount inductors and capacitors. For noise sensitive applications the LTC1878EMS8 can be externally synchronized from 400kHz to 700kHz. Burst Mode operation is inhibited during synchronization or when the SYNC/MODE pin is pulled low, preventing low frequency ripple from interfering with audio circuitry. The internal synchronous switch increases efficiency and eliminates the need for an external Schottky diode. Low output voltages are easily supported with the 0.8V feedback reference voltage. The LTC1878EMS8 is available in a space saving 8-lead MSOP package. For higher input voltage (12V abs max) applications, refer to the LTC1877 data sheet.

Parametrics

Absolute maximum ratings: (1)Input Supply Voltage (VIN): -0.3V to 7V; (2)ITH, PLL LPF Voltage: -0.3V to 2.7V; (3)RUN, VFB Voltages: -0.3V to VIN; (4)SYNC/MODE Voltage: -0.3V to VIN; (5)SW Voltage: -0.3V to (VIN + 0.3V); (6)P-Channel MOSFET Source Current (DC): 800mA; (7)N-Channel MOSFET Sink Current (DC): 800mA; (8)Peak SW Sink and Source Current: 1.5A; (9)Operating Ambient Temperature Range: -40℃ to 85℃; (10)Junction Temperature: 125℃; (11)Storage Temperature Range: -65℃ to 150℃; (12)Lead Temperature (Soldering, 10 sec): 300℃.

Features

Features: (1)High Efficiency: Up to 95%; (2)Very Low Quiescent Current: Only 10mA During Operation; (3)600mA Output Current at VIN = 3.3V; (4)2.65V to 6V Input Voltage Range; (5)550kHz Constant Frequency Operation; (6)Synchronizable from 400kHz to 700kHz; (7)Selectable Burst ModeTM Operation/Pulse Skipping Mode; (8)No Schottky Diode Required; (9)Low Dropout Operation: 100% Duty Cycle; (10)0.8V Reference Allows Low Output Voltages; (11)Shutdown Mode Draws < 1mA Supply Current; (12)±2% Output Voltage Accuracy; (13)Current Mode Control for Excellent Line and Load Transient Response; (14)Overcurrent and Overtemperature Protected; (15)Available in 8-Lead MSOP Package.

Diagrams