MIC26601 Datasheet, PDF (1/30 Pages) Micrel Semiconductor – 28V, 6A Hyper Speed Control™ Synchronous DC/DC Buck Regulator

MIC26601
28V, 6A Hyper Speed Control™
Synchronous DC/DC Buck Regulator
SuperSwitcher II™
General Description
Features
The Micrel MIC26601 is a constant-frequency, synchronous
buck regulator featuring a unique adaptive on-time control
architecture. The MIC26601 operates over an input supply
range of 4.5V to 28V and provides a regulated output of up to
6A of output current. The output voltage is adjustable down to
0.8V with a guaranteed accuracy of ±1%, and the device
operates at a switching frequency of 600kHz.
Micrel’s Hyper Speed Control™ architecture allows for ultra-
fast transient response while reducing the output capacitance
and also makes (High V_IN)/(Low V_OUT) operation possible.
This adaptive t_ON ripple control architecture combines the
advantages of fixed-frequency operation and fast transient
response in a single device.
The MIC26601 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, foldback current limit, “hiccup mode” short-
circuit protection and thermal shutdown. An open-drain
Power Good (PG) pin is provided.
All support documentation can be found on Micrel’s web
site at: www.micrel.com.
• Hyper Speed Control™ architecture enables
- High Delta V operation (V_IN = 28V and V_OUT = 0.8V)
- Small output capacitance
• 4.5V to 28V voltage input
• 6A output current capability, up to 95% efficiency
• Adjustable output from 0.8V to 5.5V
• ±1% feedback accuracy
• Any Capacitor™ stable - zero-to-high ESR
• 600kHz switching frequency
• No external compensation
• Power Good (PG) output
• Foldback current-limit and “hiccup mode” short-circuit
protection
• Supports safe startup into a pre-biased load
• –40°C to +125°C junction temperature range
• 28-pin 5mm × 6mm MLF^® package
Applications
• Distributed power systems
• Communications/networking infrastructure
• Set-top box, gateways, and routers
• Printers, scanners, graphic cards, and video cards
_________________________________________________________________________________________________________________________
Typical Application
100
95
90
85
80
75
70
65
60
55
50
0
Efficiency (VIN = 12V)
vs. Output Current
5.0V
3.3V
2.5V
1.8V
1.5V
1.2V
1.0V
0.9V
0.8V
1
2
3
4
5
6
7
8
OUTPUT CURRENT (A)
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 [phone] • fax + 1 [phone] • http://www.micrel.com
July 2011
M9999-071311-A