MIC2176-1/-2/-3
Wide Input Voltage, Synchronous Buck
Controllers Featuring Adaptive On-Time
Control
Hyper Speed Control™ Family
General Description
The Micrel MIC2176-1/-2/-3 is a family of constant-frequency,
synchronous buck controllers featuring a unique digitally
modified adaptive ON-time control architecture. The MIC2176
family operates over an input supply range of 4.5V to 75V
and can be used to supply up to 15A of output current. The
output voltage is adjustable down to 0.8V with a guaranteed
accuracy of ±1%, and the device operates at a constant
switching frequency of 100kHz, 200kHz, and 300kHz.
Micrel’s Hyper Speed Control
TM
architecture allows for ultra-
fast transient response while reducing the output capacitance
and also makes (High V
IN
)/(Low V
OUT
) operation possible.
This digitally modified adaptive t
ON
ripple control architecture
combines the advantages of fixed-frequency operation and
fast transient response in a single device.
The MIC2176 offers a full suite of protection features to
ensure protection of the IC during fault conditions. These
include undervoltage lockout to ensure proper operation
under power-sag conditions, internal soft-start to reduce
inrush current, fold-back current limit, “hiccup” mode short-
circuit protection and thermal shutdown.
All support documentation can be found on Micrel’s web
site at:
Features
•
Hyper Speed Control
TM
architecture enables
-
High delta V operation (V
IN
= 75V and V
OUT
= 1.2V)
-
Small output capacitance
4.5V to 75V input voltage
Output down to 0.8V with ±1% accuracy
Any Capacitor
TM
Stable
-
Zero-ESR to high-ESR output capacitance
100kHz/200kHz/300kHz switching frequency
Internal compensation
6ms Internal soft-start
Foldback current limit and “hiccup” mode short-circuit
protection
Thermal shutdown
Supports safe start-up into a pre-biased output
–40°C to +125°C junction temperature range
Available in 10-pin MSOP package
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Applications
•
Distributed power systems
•
Networking/Telecom Infrastructure
•
Printers, scanners, graphic cards and video cards
___________________________________________________________________________________________________________
Typical Application
Efficiency
vs. Output Current
95
90
EFFICIENCY (%)
85
80
75
70
65
60
55
50
45
40
0
1
2
3
4
5
MIC2176-2
V
OUT
= 3.3V
V
DD
= 5V LINEAR
28V
IN
48V
IN
60V
IN
OUTPUT CURRENT (A)
MIC2176-2 Adjustable Output 200KHz Buck Converter
Hyper Speed Control, SuperSwitcher II and Any Capacitor are trademarks of Micrel, Inc.
MLF and
MicroLeadFrame
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
November 2010
M9999-111710-A
MICREL [ MICREL SEMICONDUCTOR ]
