MIC26600_1107 Datasheet, PDF (1/28 Pages) Micrel Semiconductor – 7A Hyper Speed ControlTM Synchronous DC-DC Buck Regulator

MIC26600
7A Hyper Speed Control^TM
Synchronous DC-DC Buck Regulator
SuperSwitcher II^TM
General Description
The Micrel MIC26600 is a constant-frequency, synchronous
buck regulator featuring a unique digitally modified adaptive
ON-time control architecture. The MIC26600 operates over
an input supply range of 4.5V to 26V and provides a
regulated output at up to 7A of output current. The output
voltage is adjustable down to 0.8V with a typical accuracy of
±1%, and the device operates at a switching frequency of
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 MIC26600 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: www.micrel.com.
Features
• Hyper Speed Control^TM architecture enables
- High delta V operation (V_IN = 26V and V_OUT = 0.8V)
- Small output capacitance
• 4.5V to 26V input voltage
• Adjustable output from 0.8V to 5.5V (±1% accuracy)
• Any Capacitor^TM Stable
- Zero-ESR to high-ESR output capacitance
• 7A output current capability
• 300kHz switching frequency
• Internal compensation
• Up to 95% efficiency
• 6ms Internal soft-start
• Foldback current-limit and “hiccup” mode short-circuit
protection
• Thermal shutdown
• Supports safe start-up 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
Efficiency (VIN = 12V)
vs. Output Current
100
95
5.0V
90
3.3V
2.5V
85
1.8V
1.5V
1.2V
80
1.0V
0.9V
75
0.8V
70
012 3456 789
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
M9999-070111-C