MIC33050 Evaluation Board
4MHz Internal Inductor PWM Buck
Regulator with HyperLight Load
®
HyperLight Load is a trademark of Micrel, Inc.
MLF and
Micro
LeadFrame are registered trademarks of Amkor Technology, Inc.
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 24, 2014
1
Revision 4.0
General Description
The MIC33050 is a 600mA 4MHz switching regulator
featuring HyperLight Load
®
mode. The MIC33050 is
highly efficient throughout the entire output current
range, drawing just 20µA of quiescent current in
operation. The tiny 3mm x 3mm MLF
®
package, in
combination with the 4MHz switching frequency, enables
a compact sub-1mm height solution with only three
external components. The MIC33050 provides accurate
output voltage regulation under the most demanding
conditions and responds extremely quickly to a load
transient with exceptionally small output voltage ripple.
Factoring in the output current, the internal circuitry of
the MIC33050 automatically selects between two modes
of operation for optimum efficiency. Under light load
conditions, the MIC33050 goes into HyperLight Load
mode. HyperLight Load uses a pulse-frequency
modulation (PFM) control scheme that controls the off
time at light load. This proprietary architecture reduces
the amount of switching needed at light load, thereby
increasing operating efficiency. The MIC33050 attains
up to 83% efficiency at 1mA output load. As the load
current increases beyond approximately 100mA, the
device operates using the pulse-width modulation
(PWM) method for up to 93% efficiency at higher load.
The two modes of operation ensure the highest
efficiency across the entire load range.
The MIC33050 operates from an input voltage range of
2.7V to 5.5V and features internal power MOSFETs that
deliver up to 600mA of output current. This step-down
regulator provides an output voltage accuracy of ±2.5%
across the junction temperature range of
40ºC to
+125ºC. The MIC33050 is available in fixed or adjustable
versions supporting an output voltage as low as 0.7V.
Requirements
The MIC33050 evaluation board requires an input power
source that is able to deliver greater than 650mA at
2.7V. The output load can either be an active (electronic)
or passive (resistive) load.
Getting Started
1.
Connect an external supply to the V
IN
(J1)
terminal
. Apply the desired input voltage to V
IN
(J1)
and ground (J2) terminals of the evaluation board,
paying careful attention to polarity and supply
voltage (2.7V ≤ V
IN
≤ 5.5V). An ammeter may be
placed between the input supply and the V
IN
(J1)
terminal. Be sure to monitor the supply voltage at
the V
IN
(J1) terminal, since the ammeter and/or
power lead resistance can reduce the voltage
supplied to the device.
2.
Connect a load to the V
OUT
(J3) and ground
terminal (J4)
. The load can be either passive
(resistive) or active (electronic load). An ammeter
may be placed between the load and the output
terminal. Ensure the output voltage is monitored at
the V
OUT
(J3) terminal.
3.
Enable the MIC33050
. The MIC33050 evaluation
board has a pull-up resistor to V
IN
. To disable the
device, apply a voltage below 0.5V to the EN (J5)
terminal. In the absence of the pull-up resistor, the
device is enabled by applying a voltage greater than
1.2V to the EN (J5) terminal. The enable pin must be
either pulled high or low for proper operation.
Removing the pull-up resistor and leaving the pin
floating will cause the regulator to operate in an
unknown state.
Output Voltage
The MIC33050 evaluation board is available with the
following output voltage options listed in
Ordering
Information
.
Ordering Information
Part Number
Description
MIC33050-CYHL EV
1.0V Fixed Output Evaluation Board
MIC33050-4YHL EV
1.2V Fixed Output Evaluation Board
MIC33050-GYHL EV
1.8V Fixed Output Evaluation Board
MIC33050-SYHL EV
3.3V Fixed Output Evaluation Board
MIC33050-AYHL EV
Adjustable Output Evaluation Board
