MIC2111 Datasheet, PDF (1/2 Pages) Micrel Semiconductor – Single-Phase, Multi-Mode, High-Performance, Step-Down PWM Controller

MIC2111
Single-Phase, Multi-Mode,
High-Performance, Step-Down PWM
Controller
PRELIMINARY
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
MIC2111AYML
MIC2111BYML
Switching
Frequency
200kHz to 2MHz
200kHz to 2MHz
Junction
Temperature Range
−40°C to +125°C
−40°C to +125°C
Current-Sense
Gain
1 V/V
30 V/V
Package
20-Pin 3mm × 3mm TQFN
20-Pin 3mm × 3mm TQFN
Lead Finish
Pb-Free
Pb-Free
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel [phone] • fax + 1 [phone] • http://www.micrel.com
March 11, 2014
Revision 1.0