MIC4680 Datasheet, PDF (1/16 Pages) Micrel Semiconductor – 1A 200kHz SuperSwitcher™ Buck Regulator Final Information

MIC4680
Micrel
MIC4680
1A 200kHz SuperSwitcher™ Buck Regulator
Final Information
General Description
The MIC4680 SuperSwitcher™ is an easy-to-use fixed or
adjustable output voltage step-down (buck) switch-mode
voltage regulator. The 200kHz MIC4680 achieves up to 1.3A
of continuous output current over a wide input range in a
8-lead SOP (small outline package).
The MIC4680 is available in 3.3V and 5V fixed output ver-
sions or adjustable output down to 1.25V.
The MIC4680 has an input voltage range of 4V to 34V, with
excellent line, load, and transient response. The regulator
performs cycle-by-cycle current limiting and thermal shut-
down for protection under fault conditions. In shutdown
mode, the regulator draws less than 2µA of standby current.
The MIC4680 SuperSwitcher™ regulator requires a mini-
mum number of external components and can operate using
a standard series of inductors and capacitors. Frequency
compensation is provided internally for fast transient re-
sponse and ease of use.
The MIC4680 is available in the 8-lead SOP with a
–40°C to +125°C junction temperature range.
Features
• SO-8 package with up to 1.3A output current
• All surface mount solution
• Only 4 external components required
• Fixed 200kHz operation
• 3.3V, 5V, and adjustable output versions
• Internally compensated with fast transient response
• Wide 4V to 34V operating input voltage range
• Less than 2µA typical shutdown-mode current
• Up to 90% efficiency
• Thermal shutdown
• Overcurrent protection
Applications
• Simple 1A high-efficiency step-down (buck) regulator
• Replacement of TO-220 and TO-263 designs
• Efficient preregulator (5V to 2.5V, 12V to 3.3V, etc.)
• On-card switching regulators
• Positive-to-negative converter (inverting buck-boost)
• Simple battery charger
• Negative boost converter
• Higher output current regulator using external FET
Typical Applications
+6V to +34V
SHUTDOWN
ENABLE
C1
15µF
35V
Power
SOP-8
MIC4680-3.3BM
2 _IN
SW ³
1 _SHDN
FB ⁴
GND
5–8
L1
68µH
D1
B260A or
SS26
Fixed Regulator Circuit
3.3V/1A
C2
220µF
16V
+5V to +34V
SHUTDOWN
ENABLE
C1
15µF
35V
Power
SOP-8
MIC4680BM
2 _IN
SW ³
1 _SHDN
FB ⁴
GND
5–8
L1
68µH
D1
B260A or
SS26
R1
3.01k
R2
2.94k
2.5V/1A
C2
220µF
16V
Adjustable Regulator Circuit
SuperSwitcher is a trademark of Micrel, Inc.
Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 [phone] • fax + 1 [phone] • http://www.micrel.com
June 2000
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MIC4680