LM2594M-12/NOPB National Semiconductor, LM2594M-12/NOPB Datasheet - Page 8

• Manufacturer Part Number: LM2594M-12/NOPB
• Description: IC REG SIMPLE SWITCHER 8-SOIC
• Manufacturer: National Semiconductor
• Series: SIMPLE SWITCHER®r
• Type: Step-Down (Buck)r

Specifications of LM2594M-12/NOPB

• Internal Switch(s): Yes
• Synchronous Rectifier: No
• Number Of Outputs: 1
• Voltage - Output: 12V
• Current - Output: 500mA
• Frequency - Switching: 150kHz
• Voltage - Input: 4.5 ~ 40 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Primary Input Voltage: 25V
• No. Of Outputs: 1
• Output Voltage: 12V
• Output Current: 500mA
• No. Of Pins: 8
• Operating Temperature Range: -40°C To +125°C
• Filter Terminals: SMD
• Input Voltage Primary Max: 40V
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -
• Other names: *LM2594M-12; LM2594M-12

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Typical Circuit and Layout Guidelines
C
C
D1 — 1A, 40V Schottky Rectifier, 1N5819
L1 — 100 µH, L20
Select components with higher voltage ratings for designs using the LM2594HV with an input voltage between 40V and 60V.
C
C
D1 — 1A, 40V Schottky Rectifier, 1N5819
L1 — 100 µH, L20
R
C
As in any switching regulator, layout is very important. Rap-
idly switching currents associated with wiring inductance can
generate voltage transients which can cause problems. For
minimal inductance and ground loops, the wires indicated by
heavy lines should be wide printed circuit traces and
should be kept as short as possible. For best results, ex-
ternal components should be located as close to the
switcher lC as possible using ground plane construction or
single point grounding.
IN
OUT
IN
OUT
1
FF
— 1 k , 1%
— 68 µF, 35V, Aluminum Electrolytic Nichicon “PL Series”
— 68 µF, 35V, Aluminum Electrolytic Nichicon “PL Series”
— See Application Information Section
— 120 µF, 25V Aluminum Electrolytic, Nichicon “PL Series”
— 120 µF, 25V Aluminum Electrolytic, Nichicon “PL Series”
FIGURE 1. Typical Circuits and Layout Guides
Adjustable Output Voltage Versions
Fixed Output Voltage Versions
8
If open core inductors are used, special care must be
taken as to the location and positioning of this type of induc-
tor. Allowing the inductor flux to intersect sensitive feedback,
lC groundpath and C
When using the adjustable version, special care must be
taken as to the location of the feedback resistors and the as-
sociated wiring. Physically locate both resistors near the IC,
and route the wiring away from the inductor, especially an
open core type of inductor. (See application section for more
information.)
OUT
wiring can cause problems.
DS012439-23
DS012439-22