MIC2111
Single-Phase, Multi-Mode,
High-Performance, Step-Down PWM
Controller
PRELIMINARY
General Description
Features
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.
• 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
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
• 0.6V reference voltage with total ±1% accuracy for
output
• Adjustable soft-start/soft-stop and pre-biased safe
startup.
configured to operate outside audio range
when the
• Supports light load and outside audio modes
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
• Programmable
slope
compensation
and
loop
compensation
• Enable input, power-good (PG) output for sequencing
more accurate output. MIC2111 has
a
high-gain
• Programmable OCP, OVP, OTP, and dedicated FAULT
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.
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
The MIC2111 is available in a 20-pin 3mm × 3mm TQFN
package and has a junction temperature range of –40°C to
+125°C.
• Servers and work stations
• Routers, switches and networking/telecom infrastructure
• Printers, scanners, graphics and video cards
Datasheets and support documentation are available on
Micrel’s web site at: www.micrel.com.
Ordering Information
Switching
Frequency
Junction
Temperature Range
Current-Sense
Part Number
Package
Lead Finish
Gain
1 V/V
30 V/V
MIC2111AYML
MIC2111BYML
200kHz to 2MHz
200kHz to 2MHz
20-Pin 3mm × 3mm TQFN
20-Pin 3mm × 3mm TQFN
Pb-Free
Pb-Free
−40°C to +125°C
−40°C to +125°C
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
Revision 1.0
March 11, 2014