LM5116MHX

Product Summary

The LM5116MHX is a synchronous buck controller intended for step-down regulator applications from a high voltage or widely varying input supply. The control method is based upon current mode control utilizing an emulated current ramp. Current mode control provides inherent line feed-forward, cycle by cycle current limiting and ease of loop compensation. The use of emulated control ramp reduces noise sensitivity of the pulse-width modulation circuit, allowing reliable control of very small duty cycles necessary in high input voltage applications. The operating frequency is programmable from 50kHz to 1MHz. The LM5116 drives external high-side and low-side NMOS power switches with adaptive dead-time control. A user-selectable diode emulation mode enables discontinuous mode operation for improved efficiency at light load conditions. A low quiescent current sleep mode disables the controller and consumes less than 10µA of total input current. Additional features include a high voltage bias regulator, automatic switch-over to external bias for improved efficiency, thermal shutdown, frequency synchronization, cycle by cycle current limit and adjustable line under-voltage lockout.

Parametrics

LM5116MHX absolute maximum ratings: (1)VIN to GND: -0.3V to 100V; (2)VCC, VCCX, UVLO to GND (Note 3): -0.3 to 16V; (3)SW, CS to GND: -3.0 to 100V; (4)HB to SW: -0.3 to 16V; (5)HO to SW: -0.3 to HB+0.3V; (6)VOUT to GND: -0.3 to 100V; (7)CSG to GND: -1V to 1V; (8)LO to GND: -0.3 to VCC+0.3V; (9)SS to GND: -0.3 to 7V; (10)FB to GND: -0.3 to 7V; (11)DEMB to GND: -0.3 to VCC; (12)Storage Temperature Range: -55°C to +150°C; (13)Junction Temperature: +150°C.

Features

LM5116MHX features: (1)Emulated peak current mode; (2)Wide operating range up to 100V ; (3)Low IQ sleep mode (<10μA); (4)Drives standard or logic level MOSFETs; (5)Robust 2A peak gate drive; (6)Free-run or synchronous operation to 1MHz; (7)Optional diode emulation mode; (8)Programmable output from 1.215V to 80V; (9)Precision 1.5% voltage reference; (10)Programmable current limit; (11)Programmable soft-start; (12)Programmable line under-voltage lockout; (13)Automatic switch to external bias supply; (14)TSSOP-20EP exposed pad; (15)Thermal shutdown.

Diagrams