MIC4680-3.3BM Micrel Inc, MIC4680-3.3BM Datasheet - Page 10

• Manufacturer Part Number: MIC4680-3.3BM
• Description: IC REG BUCK 1A 3.3V 8SOIC
• Manufacturer: Micrel Inc
• Series: SuperSwitcher™r
• Type: Step-Down (Buck)r

Specifications of MIC4680-3.3BM

• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Internal Switch(s): Yes
• Synchronous Rectifier: No
• Number Of Outputs: 1
• Voltage - Output: 3.3V
• Current - Output: 1A
• Frequency - Switching: 200kHz
• Voltage - Input: 4 ~ 34 V
• Operating Temperature: -40°C ~ 125°C
• Output Current: 1.3A
• Output Voltage: 3.3VDC
• No. Of Pins: 8
• Peak Reflow Compatible (260 C): No
• Leaded Process Compatible: No
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant, Lead free / RoHS Compliant

Applications Information
Adjustable Regulators
Adjustable regulators require a 1.23V feedback signal.
Recommended
common output voltages are included in Figure 1b.
For other voltages, the resistor values can be
determined using the following formulas:
*
**
***
†
Micrel, Inc.
March 2008
V
1.8V
2.5V
3.3V
5.0V
6.0V
OUT
All resistors 1%
Shielded magnetics for low RFI applications
Vishay-Diode, Inc. (805) 446-48600
Nearest available resistor values
V
R1
3.01k
3.01k
3.01k
3.01k
3.01k
V
R1*†
REF
OUT
=
= 1.23V
R2
=
6.495k
2.915k
1.788k
⎛
⎜ ⎜
⎝
982Ω
776Ω
V
R2*†
V
voltage-divider
V
REF
OUT
REF
⎛
⎜
⎝
R2
R1
−
AVX TPSE156035R0200
1
+
⎞
⎟ ⎟
⎠
Figure 1b. Recommended Components for Common Output Voltages
,
1
⎞
⎟
⎠
R
15µF 35V
2
=
C
IN
resistor
V
V
OUT
REF
R1
−
1
values
SS26 General Semiconductor
B260A Vishay-Diode, Inc***
2A 60V Schottky
for
D1
or
10
SHUTDOWN
ENABLE
Figure 1a. Adjustable Regulator Circuit
V
Sumida CDRH125-680MC**
Sumida CDRH124-680MC**
IN
C
Coiltronics UP2B-680
IN
68µH 1.5A
2
1
IN
SHDN
L1
MIC4680BM
or
or
GND
5–8
SW
FB
3
4
D1
AVX TPSE227010R0060
L1
220µF 10V
M9999-032808
C
OUT
R1
R2
MIC4680
V
C
OUT
OUT