MIC4574-3.3BWM Micrel Semiconductor, MIC4574-3.3BWM Datasheet

no-image

MIC4574-3.3BWM

Manufacturer Part Number
MIC4574-3.3BWM
Description
200kHz Simple 0.5A Buck Voltage Regulator
Manufacturer
Micrel Semiconductor
Datasheet

Available stocks

Company
Part Number
Manufacturer
Quantity
Price
Part Number:
MIC4574-3.3BWM
Manufacturer:
MICREL
Quantity:
9 922
MIC4574
General Description
The MIC4574 is a series of easy to use fixed and adjustable
BiCMOS step-down (buck) switch-mode voltage regulators.
The 200kHz MIC4574 duplicates the pinout and function of
the 52kHz LM2574. The higher switching frequency may
allow up to a 2:1 reduction in output filter inductor size.
The MIC4574 is available in 3.3V, and 5V fixed output
versions or a 1.23V to 20V adjustable output version. Both
versions are capable of driving a 0.5A load with excellent line
and load regulation.
The feedback voltage is guaranteed to 2% tolerance for
adjustable versions, and the output voltage is guaranteed to
conditions. The oscillator frequency is guaranteed to 10%.
In shutdown mode, the regulator draws less than 200 A
standby current.
current limiting and thermal shutdown for protection under
fault conditions.
This series of simple switch-mode regulators requires a
minimum number of external components and can operate
using a standard series of inductors. Frequency compensa-
tion is provided internally.
The MIC4574 is available in DIP (N) and SOIC (WM) pack-
ages for the industrial temperature range.
Typical Applications
3% for fixed versions, within specified voltages and load
The regulator performs cycle-by-cycle
6V to 24V
Shutdown
Enable
10µF
35V
C1
8V to 24V
Shutdown
Enable
10
5
47µF
35V
C1
SHDN
V
SGND
IN
MIC4574BWM
4
3
5
SHDN
V
PGND
MIC4574-5.0BN
IN
SGND
Adjustable Regulator
SW
6
FB
2
Fixed Regulator
12
3
PGND
4-92
4
SW
FB
D1
MBRS130LT3
100µH
Features
• Fixed 200kHz operation
• 3.3V, 5V, and adjustable output versions
• Voltage over specified line and load conditions:
• Guaranteed 0.5A switch current
• Wide 4V to 24V input voltage range
• Wide 1.23V to 20V output voltage range
• Requires minimum external components
• < 200 A typical shutdown mode
• 75% efficiency (adjustable version > 75% typ.)
• Standard inductors and capacitors are
• Thermal shutdown
• Overcurrent protection
• 100% electrical thermal limit burn-in
Applications
• Simple high-efficiency step-down (buck) regulator
• Efficient preregulator for linear regulators
• On-card switching regulators
• Positive-to-negative converter (inverting buck-boost)
• Isolated flyback converter using minimum external
• Negative boost converter
L1
200kHz Simple 0.5A Buck Voltage Regulator
7
1
25% of typical LM2574 values
components
Fixed version: 3% max. output voltage
Adjustable version: 2% max. feedback voltage
D1
1N5819
100µH
R2
2.49k
1%
R1
1.50k
1%
L1
5.0V/0.5A
C3
3300pF
C2
220µF
16V
MIC4574
3.3V/0.5A
C2
330µF
6.3V
April 1998•
Micrel

Related parts for MIC4574-3.3BWM

Related keywords