Features: *3.3V, 5V, 12V, and adjustable output versions
* Adjustable version output voltage range, 1.2V to 37V (57V for the HV version)±4% max over line and load conditions
*Available in 8-pin surface mount and DIP-8 package
* Guaranteed 0.5A output current
* Input voltage range up to 60V
* Requires only 4 external components
* 150 kHz fixed frequency internal oscillator
* TTL Shutdown capability
* Low power standby mode, IQ typically 85 A
* High Efficiency
* Uses readily available standard inductors
* Thermal shutdown and current limit protectionApplicationSimple high-efficiency step-down (buck) regulator
Efficient pre-regulator for linear regulators
On-card switching regulators
Positive to Negative convertorPinout
Specifications
| Output Current |
500 mA |
| Input Min Voltage |
4.5, 7, 4.75, 15 Volt |
| Input Max Voltage |
60 Volt |
| Output Min |
3.3, 1.23, 12, 5 Volt |
| Output Max |
57, 3.3, 12, 5 Volt |
| Frequency Min |
150 kHz |
| Frequency Max |
150 kHz |
| Efficiency (peak) |
88, 80, 82 % |
| On/Off Pin |
Yes |
| Error Flag |
Yes |
| SoftStart |
No |
| Sync Pin |
No |
| Flyback |
No |
| RegType |
Switching Regulator |
| Temperature Min |
-40 deg C |
| Temperature Max |
125 deg C |
| Adjustable Output |
Yes, No |
| Adj Switch Frequency |
No |
| PWM Mode |
Voltage |
| Topology |
Buck |
| Special Features |
SIMPLE SWITCHER regulator |
| Step-Down |
Yes |
| Multiple Output Capability |
No |
| Output Power |
Undefined Watt |
| Output Voltage |
3.3, Undefined, 12, 5 Volt |
| Output Range |
5V, 12V, 3.3V, 1.23V to 57V |
| Switching Frequency |
150 kHz |
| Regulator Family |
SIMPLE SWITCHER |
| AEC Q-100 Automotive Grade |
Undefined |
| Synchronous Rectification |
No |
| View Using Catalog |
If Military/Aerospace specified devices are required,pleasecontacttheNationalSemiconductorSalesOffice/Distributors for availability and specifications.
Maximum Supply Voltage
LM2594 45V
LM2594HV 60V
ON /OFF Pin Input Voltage -0.3 V +25V
Feedback Pin Voltage -0.3 V +25V
Output Voltage to Ground
(Steady State) -1V
Power Dissipation Internally limited
Storage Temperature Range -65 to +150
Human Body Model (Note 2) 2 kV
Lead Temperature
M8 Package
Vapor Phase (60 sec.)
Infrared (15 sec.)+215
N Package (Soldering, 10 sec.)+220
Maximum Junction Temperature+260
ESD Susceptibility +150
DescriptionThe LM2594/LM2594HV 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, and an adjustable output version, and are packaged in a 8-lead DIP and a 8-lead surface mount package.
Requiring a minimum number of external components, these regulators are simple to use and feature internal frequency compensation†, a fixed-frequency oscillator, and improved line and load regulation specifications.
The LM2594/LM2594HV series operates at a switching frequency of 150 kHz thus allowing smaller sized filter components than what would be needed with lower frequency switching 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 (both through hole and surface mount types) are available from several different manufacturers optimized for use with the LM2594/LM2594HV series. This feature greatly simplifies the design of switch-mode power supplies.
Other features include a guaranteed ±4% tolerance on output voltage under all conditions of input voltage and output load conditions, and ±15% on the oscillator frequency. External shutdown is included, featuring typically 85µA standby current. Self protection features include a two stage frequency reducing current limit for the output switch and an over temperature shutdown for complete protection under fault conditions.
The LM2594HV is for applications requiring an input voltage up to 60V.
Reliability Metrics
| Part Number |
Process |
EFR Reject |
EFR Sample Size |
PPM |
LTA Rejects |
LTA Device Hours |
FITS |
MTTF (Hours) |
| LM2594HVM-12 |
LB300 |
0 |
32249 |
0 |
0 |
3406500 |
2 |
966603676 |
| LM2594HVM-3.3 |
LB300 |
0 |
32249 |
0 |
0 |
3406500 |
2 |
966603676 |
| LM2594HVM-5.0 |
LB300 |
0 |
32249 |
0 |
0 |
3406500 |
2 |
966603676 |
| LM2594HVM-ADJ |
LB300 |
0 |
32249 |
0 |
0 |
3406500 |
2 |
966603676 |
| LM2594HVMX-12 |
LB300 |
0 |
32249 |
0 |
0 |
3406500 |
2 |
966603676 |
| LM2594HVMX-3.3 |
LB300 |
0 |
32249 |
0 |
0 |
3406500 |
2 |
966603676 |
| LM2594HVMX-5.0 |
LB300 |
0 |
32249 |
0 |
0 |
3406500 |
2 |
966603676 |
| LM2594HVMX-ADJ |
LB300 |
0 |
32249 |
0 |
0 |
3406500 |
2 |
966603676 |
| LM2594HVN-12 |
LB300 |
0 |
32249 |
0 |
0 |
3406500 |
2 |
966603676 |
| LM2594HVN-3.3 |
LB300 |
0 |
32249 |
0 |
0 |
3406500 |
2 |
966603676 |
| LM2594HVN-5.0 |
LB300 |
0 |
32249 |
0 |
0 |
3406500 |
2 |
966603676 |
| LM2594HVN-ADJ |
LB300 |
0 |
32249 |
0 |
0 |
3406500 |
2 |
966603676 |
Note: The Early Failure Rates (EFR) were calculated as point estimate PPM based on rejects and sample size for EFR. The Long Term Failure Rates were calculated at 60% confidence using the Arrhenius equation at 0.7eV activation energy and derating the assumed stress temperature of 150°C to an application temperature of 55°C.For more information on Reliability Metrics, please click here.
LM2594HV Data Sheet
