LM3578A

Features:

Inverting and non-inverting feedback inputs
1.0V reference at inputs
Operates from supply voltages of 2V to 40V
Output current up to 750 mA, saturation less than 0.9V
Current limit and thermal shut down
Duty cycle up to 90%




Application

Switching regulators in buck, boost, inverting, and single-ended transformer configurations
Motor speed control
Lamp flasher

Specifications

Output Current	750 mA
Input Min Voltage	Undefined Volt
Input Max Voltage	40 Volt
Output Min	1 Volt
Output Max	Undefined Volt
Frequency Min	1 kHz
Frequency Max	100 kHz
On/Off Pin	No
Error Flag	No
SoftStart	No
Sync Pin	No
Inverting	Yes
Flyback	Yes
RegType	Switching Regulator
Temperature Min	0 deg C
Temperature Max	125 deg C
Adjustable Output	Yes
Adj Switch Frequency	Yes
PWM Mode	Voltage
Topology	Buck, Boost, Flyback, Inverting
Special Features	FB and NFB pins
Step-Down	Yes
Multiple Output Capability	No
Output Power	Undefined Watt
Output Voltage	Undefined Volt
Output Range	Undefined
Switching Frequency	20 kHz
Feedback Voltage	1 Volt
Regulator Family	Undefined
AEC Q-100 Automotive Grade	Undefined
Synchronous Rectification	No
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Description

The LM3578A is a switching regulator which can easily be set up for such DC-to-DC voltage conversion circuits as the buck, boost, and inverting configurations. The LM1578A features a unique comparator input stage which not only has separate pins for both the inverting and non-inverting inputs, but also provides an internal 1.0V reference to each input, thereby simplifying circuit design and p.c. board layout. The output can switch up to 750 mA and has output pins for its collector and emitter to promote design flexibility. An external current limit terminal may be referenced to either the ground or the Vin terminal, depending upon the application. In addition,
the LM1578A has an on board oscillator, which sets the switching frequency with a single external capacitor from <1 Hz to 100 kHz (typical).

The LM3578A is an improved version of the LM1578, offering higher maximum ratings for the total supply voltage and output transistor emitter and collector voltages.

The LM3578A is a switching regulator which can easily be set up for such DC-to-DC voltage conversion circuits as the buck, boost, and inverting configurations. The LM2578A features a unique comparator input stage which not only has separate pins for both the inverting and non-inverting inputs, but also provides an internal 1.0V reference to each input, thereby simplifying circuit design and p.c. board layout. The output can switch up to 750 mA and has output pins for its collector and emitter to promote design flexibility. An external current limit terminal may be referenced to either the ground or the V_in terminal, depending upon the application. In addition, the LM2578A has an on board oscillator, which sets the switching frequency with a single external capacitor from <1 Hz to 100 kHz (typical).

The LM3578A is an improved version of the LM2578, offering higher maximum ratings for the total supply voltage and output transistor emitter and collector voltages.

Reliability Metrics

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Part Number	Process	EFR Reject	EFR Sample Size	PPM	LTA Rejects	LTA Device Hours	FITS	MTTF (Hours)
LM3578AM	SLM	0	42786	0	0	3352500	2	951281028
LM3578AMX	SLM	0	42786	0	0	3352500	2	951281028
LM3578AN	SLM	0	42786	0	0	3352500	2	951281028

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.

Application Notes

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Title	Size in Kbytes	Date
AN-1066: Application Note 1066 Low Cost Boost Converters Using LM3578A	206 Kbytes	26-Sep-02	Download
AN-1055: AN-1055 Low-Cost Multiple Output Flyback Converter for I/O Cards	88 Kbytes	5-Jan-97	Download
AN-1889: Application Note 1889 How to Measure the Loop Transfer Function of Power Supplies	612 Kbytes	14-Oct-08	Download

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