LM2578AM/NOPB National Semiconductor, LM2578AM/NOPB Datasheet - Page 6

• Manufacturer Part Number: LM2578AM/NOPB
• Description: IC REG SIMPLE SWITCHER 8-SOIC
• Manufacturer: National Semiconductor
• Type: Step-Down (Buck), Step-Up (Boost), Inverting, Flybackr

Specifications of LM2578AM/NOPB

• Internal Switch(s): Yes
• Synchronous Rectifier: No
• Number Of Outputs: 1
• Current - Output: 750mA
• Frequency - Switching: 20kHz
• Voltage - Input: 2 ~ 40 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Primary Input Voltage: 40V
• No. Of Outputs: 1
• Output Current: 750mA
• No. Of Pins: 8
• Operating Temperature Range: -40°C To +85°C
• Msl: MSL 1 - Unlimited
• Input Voltage Primary Max: 40V
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Voltage - Output: -
• Power - Output: -
• Other names: *LM2578AM; *LM2578AM/NOPB; LM2578AM

www.national.com
Typical Performance Characteristics
Test Circuit*
Parameter tests can be made using the test circuit shown.
Select the desired V
adjustable power supplies. A digital volt meter with an input
resistance greater than 100 MΩ should be used to measure
the following:
Input Reference Voltage to Ground; S1 in either position.
Level Shift Accuracy (%) = (T
= 1 mA
Input Current (mA) = (1V − T
0 mA.
Oscillator parameters can be measured at T
quency counter or an oscilloscope.
Current Limit Sense Voltage
in
vs Supply Voltage
, collector voltage and duty cycle with
Supply Current
P3
p3
(V)/1V) x 100%; S1 at I
(V))/1 MΩ: S1 at I
p4
00871140
00871142
using a fre-
1
= I
1
= I
2
=
2
6
(Continued)
The Current Limit Sense Voltage is measured by connecting
an adjustable 0-to-1V floating power supply in series with the
current limit terminal and referring it to either the ground or
the V
point T
until the LM2578A’s duty cycle just reaches 0%. This voltage
is the Current Limit Sense Voltage.
The Supply Current should be measured with the duty cycle
at 0% and S1 in the I
*LM2578A specifications are measured using automated
test equipment. This circuit is provided for the customer’s
convenience when checking parameters. Due to possible
variations in testing conditions, the measured values from
these testing procedures may not match those of the factory.
in
P5
terminal. Set the duty cycle to 90% and monitor test
while adjusting the floating power supply voltage
Emitter Output Below Ground
Collector Current with
Supply Current
1
= I
2
= 0 mA position.
00871141
00871143