MIC2128YML-TR Microchip

MIC2128 75V, Synchronous Buck Controller Featuring Adaptive On-Time Control with External Soft Start Features General Description The MIC2128 is a constant-frequency synchronous Hyper Speed Control Architecture Enables: buck controller featuring a unique adaptive on-time - High Input to Output Voltage Conversion control architecture with external soft start. The Ratio Capability MIC2128 operates over an input voltage range from - Any Capacitor Stable 4.5V to 75V.The output voltage is adjustable down to - Ultra-Fast Load Transient Response 0.6V with a guaranteed accuracy of 1%. The device Wide 4.5V to 75V Input Voltage Range operates with programmable switching frequency from 270 kHz to 800 kHz. Adjustable Output Voltage from 0.6V to 30V The MIC2128 features an external soft-start pin (SS) 270 kHz to 800 kHz Programmable Switching which allows the user to adjust output soft-start time to Frequency reduce inrush current from mains during start-up. The Built-in 5V Regulator for Single-Supply Operation MIC2128 features an auxiliary bootstrap LDO which Auxiliary Bootstrap LDO for Improving System improves the system efficiency by supplying the Efficiency MIC2128 internal circuit bias power and gate drivers Internal Bootstrap Diode from output of the converter. A logic level enable (EN) Adjustable Soft-Start Time signal can be used to enable or disable the Enable Input and Power Good Output controller.The MIC2128 can start-up monotonically into a prebiased output. The MIC2128 features an open Programmable Current Limit drain power good signal (PG) which signals when the Hiccup Mode Short-Circuit Protection output is in regulation and can be used for simple Internal Compensation and Thermal Shutdown power supply sequencing purpose. Supports Safe Start-Up into a Prebiased Output The MIC2128 offers a full suite of protection features to ensure protection of the IC during Fault conditions. Applications These include undervoltage lockout to ensure proper operation under power-sag conditions, hiccup mode Networking/Telecom Equipment short-circuit protection and thermal shutdown. Base Station, Servers The MIC2128 is available in a 16-pin 3 mm x 3 mm Distributed Power Systems QFN package, with an operating junction temperature Industrial Power Supplies range from -40C to +125C. Package Types MIC2128 3x3 QFN* (Top View) 13 16 15 14 PG 1 SS 12 I 11 LIM 2 FREQ EP SW 3 10 EN BST 9 4 EXTVDD 56 7 8 * Includes Exposed Thermal Pad (EP) see Table 3-1. 2017 Microchip Technology Inc. DS20005620B-page 1 DH V IN P V GND DD DL A GND FB P VDDMIC2128 Typical Application V V IN P IN VDD 4.5V to 75V 4.7 F 0.1 F 2.2 FX3 Q1 DH 2.2 BST L1 V DD 0.1 F 10 H V OUT 4.7 F SW 5V 5A C1 + MIC2128 330 F 47 F I LIM 1.5 k 0.1 F PG Q2 DL 7.5 k 4.7 nF EN V IN 18 k SS 10 nF FB 1 k 100 k EXTVDD V OUT FREQ V IN 1 F A P GND GND 60 k Q1,Q2: SiR878ADP L1: SRP1265A-100M, Bourns C1: 10SVP330M Functional Block Diagram EXTVDD V P EN V DD VDD IN 9 15 8 10 16 LINEAR LINEAR REGULATOR REGULATOR UVLO 4 BST THERMAL SHUTDOWN DH 5 T ON 11 FREQ ESTIMATION Control Negative Current 3 SW Logic Limit COMPENSATION P VDD 13 FB g m 1.3 A DL 7 12 SS V REF 0.6V CURRENT LIMIT 96 A DETECTION 2 I LIM PG 1 V 0.9 REF 6 P GND FB 14 AGND DS20005620B-page 2 2017 Microchip Technology Inc.