MC34167_05 Datasheet, PDF (1/20 Pages) ON Semiconductor – 5.0 A, Step−Up/Down/Inverting Switching Regulators

MC34167, MC33167
5.0 A, Step−Up/Down/
Inverting Switching
Regulators
The MC34167, MC33167 series are high performance fixed
frequency power switching regulators that contain the primary
functions required for dc−to−dc converters. This series was
specifically designed to be incorporated in step−down and
voltage−inverting configurations with a minimum number of external
components and can also be used cost effectively in step−up
applications.
These devices consist of an internal temperature compensated
reference, fixed frequency oscillator with on−chip timing components,
latching pulse width modulator for single pulse metering, high gain
error amplifier, and a high current output switch.
Protective features consist of cycle−by−cycle current limiting,
undervoltage lockout, and thermal shutdown. Also included is a low
power standby mode that reduces power supply current to 36 mA.
Features
• Output Switch Current in Excess of 5.0 A
• Fixed Frequency Oscillator (72 kHz) with On−Chip Timing
• Provides 5.05 V Output without External Resistor Divider
• Precision 2% Reference
• 0% to 95% Output Duty Cycle
• Cycle−by−Cycle Current Limiting
• Undervoltage Lockout with Hysteresis
• Internal Thermal Shutdown
• Operation from 7.5 V to 40 V
• Standby Mode Reduces Power Supply Current to 36 mA
• Economical 5−Lead TO−220 Package with Two Optional Leadforms
• Also Available in Surface Mount D²PAK Package
• Moisture Sensitivity Level (MSL) Equals 1
• Pb−Free Packages are Available
I_LIMIT
V_in
4
Oscillator
S
Q
R
2
PWM
Thermal
UVLO
Reference
EA
1
3
5
This device contains 143 active transistors.
Figure 1. Simplified Block Diagram
(Step Down Application)
L
V_O
5.05 V/
5.0 A
http://onsemi.com
MARKING
DIAGRAMS
1
5
TO−220
TH SUFFIX
CASE 314A
MC
3x167T
AWLYWWG
Heatsink surface connected to Pin 3
1
5
TO−220
TV SUFFIX
CASE 314B
MC
3x167T
AWLYWWG
TO−220
1
T SUFFIX
CASE 314D
5
Pin 1. Voltage Feedback Input
2. Switch Output
3. Ground
4. Input Voltage/V_CC
5. Compensation/Standby
MC
3x167T
AWLYWWG
D²PAK
MC
1
D2T SUFFIX
CASE 936A
3x167T
AWLYWWG
5
Heatsink surface (shown as
terminal 6 in case outline
1
5
drawing) is connected to Pin 3
x = 3 or 4
A = Assembly Location
WL = Wafer Lot
Y = Year
WW = Work Week
G = Pb−Free Package
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 17 of this data sheet.
© Semiconductor Components Industries, LLC, 2005
1
November, 2005 − Rev. 7
Publication Order Number:
MC34167/D