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Details, datasheet, quote on part number:LM2574-12
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| Part: | LM2574-12 |
| Category: | Power Management => Regulators => Switching Regulators |
| Description: | LM2574 - Simple Switcher 0.5A Step-down Voltage Regulator, Package: Soic Wide, Pin Nb=14 |
| Company: | National Semiconductor Corporation |
| Datasheet: | Download LM2574-12 datasheet File size : 655 kB |
| Request For quote: | Find where to buy LM2574-12
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Datasheet text preview:
LM2574/LM2574HV SIMPLE SWITCHER 0.5A Step-Down Voltage Regulator
June 1999
LM2574/LM2574HV SIMPLE SWITCHERTM 0.5A Step-Down Voltage Regulator
General Description
The LM2574 series of regulators are monolithic integrated circuits that provide all the active functions for a step-down (buck) switching regulator, capable of driving a 0.5A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3V, 5V, 12V, 15V, and an adjustable output version. Requiring a minimum number of external components, these regulators are simple to use and include internal frequency compensation and a fixed-frequency oscillator. The LM2574 series offers a high-efficiency replacement for popular three-terminal linear regulators. Because of its high efficiency, the copper traces on the printed circuit board are normally the only heat sinking needed. A standard series of inductors optimized for use with the LM2574 are available from several different manufacturers. This feature greatly simplifies the design of switch-mode power supplies. Other features include a guaranteed ± 4% tolerance on output voltage within specified input voltages and output load conditions, and ± 10% on the oscillator frequency. External shutdown is included, featuring 50 µA (typical) standby current. The output switch includes cycle-by-cycle current limiting, as well as thermal shutdown for full protection under fault conditions.
Features
n 3.3V, 5V, 12V, 15V, and adjustable output versions n Adjustable version output voltage range, 1.23V to 37V (57V for HV version) ± 4% max over line and load conditions n Guaranteed 0.5A output current n Wide input voltage range, 40V, up to 60V for HV version n Requires only 4 external components n 52 kHz fixed frequency internal oscillator n TTL shutdown capability, low power standby mode n High efficiency n Uses readily available standard inductors n Thermal shutdown and current limit protection
Applications
n n n n Simple high-efficiency step-down (buck) regulator Efficient pre-regulator for linear regulators On-card switching regulators Positive to negative converter (Buck-Boost)
Typical Application
(Fixed Output Voltage Versions)
DS011394-1
Note: Pin numbers are for 8-pin DIP package.
Patent Pending SIMPLE SWITCHERTM is a trademark of National Semiconductor Corporation
© 1999 National Semiconductor Corporation
DS011394
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Connection Diagrams
8-Lead DIP 14-Lead Wide Surface Mount (WM)
DS011394-2
* No internal connection, but should be soldered to PC board for best heat transfer.
Top View Order Number LM2574-3.3HVN, LM2574HVN-5.0, LM2574HVN-12, LM2574HVN-15, LM2574HVN-ADJ, LM2574N-3.3, LM2574N-5.0, LM2574N-12, LM2574N-15 or LM2574N-ADJ See NS Package Number N08A
DS011394-3
Top View Order Number LM2574HVM-3.3, LM2574HVM-5.0, LM2574HVM-12, LM2574HVM-15, LM2574HVM-ADJ, LM2574M-3.3 LM2574M-5.0, LM2574M-12, LM2574M-15 or LM2574M-ADJ See NS Package Number M14B
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Absolute Maximum Ratings (Note 1)
If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Maximum Supply Voltage LM2574 LM2574HV ON /OFF Pin Input Voltage Output Voltage to Ground (Steady State) Minimum ESD Rating (C = 100 pF, R = 1.5 k) Storage Temperature Range 45V 63V -0.3V V +VIN -1V 2 kV -65°C to +150°C
Lead Temperature (Soldering, 10 seconds) Maximum Junction Temperature Power Dissipation
260°C 150°C Internally Limited
Operating Ratings
Temperature Range LM2574/LM2574HV Supply Voltage LM2574 LM2574HV -40°C TJ +125°C 40V 60V
LM2574-3.3, LM2574HV-3.3 Electrical Characteristics
Specifications with standard type face are for TJ = 25°C, and those with boldface type apply over full Operating Temperature Range. Symbol Parameter Conditions Typ SYSTEM PARAMETERS (Note 3) Test Circuit Figure 2 VOUT Output Voltage VIN = 12V, ILOAD = 100 mA LM2574-3.3 LM2574HV-3.3 Limit (Note 2) 3.3 3.234 3.366 VOUT Output Voltage LM2574 VOUT Output Voltage LM2574HV Efficiency VIN = 12V, ILOAD = 0.5A 72 4.75V VIN 60V, 0.1A ILOAD 0.5A 3.3 3.168/3.135 3.450/3.482 V(Min) V(Max) % 4.75V VIN 40V, 0.1A ILOAD 0.5A 3.3 3.168/3.135 3.432/3.465 V V(Min) V(Max) V V(Min) V(Max) Units (Limits)
LM2574-5.0, LM2574HV-5.0 Electrical Characteristics
Specifications with standard type face are for TJ = 25°C, and those with boldface type apply over full Operating Temperature Range. Symbol Parameter Conditions Typ SYSTEM PARAMETERS (Note 3) Test Circuit Figure 2 VOUT Output Voltage VIN = 12V, ILOAD = 100 mA LM2574-5.0 LM2574HV-5.0 Limit (Note 2) 5 4.900 5.100 VOUT Output Voltage LM2574 VOUT Output Voltage LM2574HV Efficiency VIN = 12V, ILOAD = 0.5A 77 7V VIN 60V, 0.1A ILOAD 0.5A 5 4.800/4.750 5.225/5.275 V(Min) V(Max) % 7V VIN 40V, 0.1A ILOAD 0.5A 5 4.800/4.750 5.200/5.250 V V(Min) V(Max) V V(Min) V(Max) Units (Limits)
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