MIC2111

Single-Phase, Multi-Mode,

High-Performance, Step-Down PWM

Controller

PRELIMINARY

Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com

March 11, 2014

Revision 1.0

General Description

Micrel’s MIC2111 is a programmable-frequency, valley-

current/voltage-mode PWM controller that provides the

control and protection features necessary for a high-

current, step-down DC-to-DC converter. The MIC2111 is

compatible with power devices and drivers which use

current sensing across the inductor. MIC2111 can provide

single tri-state or dual non-tri-state PWM logic signals to

work with either power-stage modules or discrete driver

MOSFETs. MIC2111 has precision enable and power

good (PG) functions for sequencing of multiple power

supply.

The MIC2111 frequency can be programmed from 200kHz

to 2MHz to optimize system size and system efficiency.

The device operates in power-saving mode at light loads

by reducing the switching frequency. The device can be

configured to operate outside audio range

when the

external power stage is configured for light load mode. The

MIC2111 uses differential current sensing for better

current-limit accuracy and also includes a dedicated

differential amplifier for remote output sensing to provide a

more

accurate

output.

MIC2111

has

a

high-gain

transconductance

amplifier

for

loop

compensation.

External slope compensation can be added through a

resistor to avoid sub-harmonic oscillations. The MIC2111

has

programmable

OCP,

OVP,

and

thermal

OTP

protections as well as a dedicated FAULT pin for accurate

system startup/stop in fault conditions.

The MIC2111 is available in a 20-pin 3mm × 3mm TQFN

package and has a junction temperature range of –40

°C to

+125

°C.

Datasheets and support documentation are available on

Micrel’s web site at: www.micrel.com.

Features

• Single 3.3V or 5V supply

• Supports load currents more than 50A

• Programmable valley-current/voltage-mode PWM

architecture

• 3.3V logic PWM outputs compatible with power-stage

modules and DrMOS modules

• Single tri-state PWM output

• Programmable switching frequency: 200kHz to 2MHz.

• Differential remote sensing for output voltage and

inductor current

• 0.6V reference voltage with total ±1% accuracy for

output

• Adjustable soft-start/soft-stop and pre-biased safe

startup.

• Supports light load and outside audio modes

• Programmable

slope

compensation

and

loop

compensation

• Enable input, power-good (PG) output for sequencing

• Programmable OCP, OVP, OTP, and dedicated FAULT

pin for system safe startup/stop

• Internal thermal shutdown and UVLO

• –40°C to +125°C junction temperature range

• Available in 20-pin 3mm × 3mm TQFN package

Applications

• Servers and work stations

• Routers, switches and networking/telecom infrastructure

• Printers, scanners, graphics and video cards

Ordering Information

Part Number

Switching

Frequency

Junction

Temperature Range

Current-Sense

Gain

Package

Lead Finish

MIC2111AYML

200kHz to 2MHz

−40°C to +125°C

1 V/V

20-Pin 3mm × 3mm TQFN

Pb-Free

MIC2111BYML

200kHz to 2MHz

−40°C to +125°C

30 V/V

20-Pin 3mm × 3mm TQFN

Pb-Free