Product Summary

The LM1770TMFX is an efficient synchronous buck switching controller in a tiny SOT23 package. The constant on-time contro scheme provides a simple design free of compensation components, allowing minimal component count and board space. It also incorporates a unique input feed-forward to maintain a constant frequency independent of the input voltage. The LM1770TMFX is optimized for a low voltage input range of 2.8V to 5.5V and can provide an adjustable output as low as 0.8V. Driving an external high side PFET and low side NFET it can provide efficiencies as high as 95%. The applicaitons of the LM1770TMFX are (1)Simple To Design, High Efficiency Step Down Switching Regulators; (2)Set-Top Boxes; (3)Cable Modems; (4)Printers; (5)Digital Video Recorders; (6)Servers.

Parametrics

LM1770TMFX absolute maximum ratings: (1)VIN: -0.3V to 6V; (2)Storage Temperature Range: -65 to 150℃; (3)Junction Temperature: 150℃; (4)Lead Temperature (soldering, 10sec): 260℃; (5)ESD Rating: 2.5kV.

Features

LM1770TMFX features: (1)Input voltage range of 2.8V to 5.5V; (2)0.8V reference voltage; (3)No compensation required; (4)Constant frequency across input range; (5)Low quiescent current of 400μA; (6)Internal soft-start; (7)Short circuit protection; (8)Tiny SOT-23 package.

Diagrams

LM1770TMFX block diagram

Image Part No Mfg Description Data Sheet Download Pricing
(USD)		 Quantity
LM1770TMFX
LM1770TMFX
National Semiconductor (TI)
DC/DC Switching Controllers
Data Sheet
0-3000: $0.59
3000-6000: $0.57
6000-12000: $0.55
LM1770TMFX/NOPB
LM1770TMFX/NOPB
National Semiconductor (TI)
DC/DC Switching Controllers
Data Sheet
0-2140: $0.59
2140-3000: $0.59
3000-5000: $0.57
5000-10000: $0.55