DC1194A Linear Technology, DC1194A Datasheet - Page 11

• Manufacturer Part Number: DC1194A
• Description: BOARD EVAL LTM8020
• Manufacturer: Linear Technology
• Series: µModuler

Specifications of DC1194A

• Design Resources: LTM8020 Spice Model LTM8020 Gerber Files DC1194A Design File DC1194A Schematic
• Main Purpose: DC/DC, Step Down
• Outputs And Type: 1, Non-Isolated
• Power - Output: -
• Voltage - Output: 3.3V
• Current - Output: 200mA
• Voltage - Input: 4.5 ~ 36 V
• Regulator Topology: Buck
• Frequency - Switching: 450kHz
• Board Type: Fully Populated
• Utilized Ic / Part: LTM8020
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

APPLICATIONS INFORMATION
Minimum Input Voltage
The LTM8020 is a step-down converter, so a minimum
amount of headroom is required to keep the output in
regulation. For most applications at full load, the input
needs to be at least 1.5V above the desired output. In
addition, the input voltage required to turn on depends
upon how the SHDN pin is tied. It takes more input voltage
to turn on if SHDN is tied to V
controlled by raising SHDN when V
operating range. A graph of the input voltage required to
turn the LTM8020 on when SHDN is tied to V
SHDN is switched is given in the Typical Performance
Characteristics section.
Table 1. Recommended External Component Values and Configuration
V
4.5V - 36V
4.5V - 36V
4.5V - 36V
4.5V - 36V
4.5V - 36V
6.5V - 36V
4.5V - 15V
4.5V - 15V
4.5V - 15V
4.5V - 15V
4.5V - 15V
6.5V - 15V
9V - 24V
9V - 24V
9V - 24V
9V - 24V
9V - 24V
9V - 24V
18V - 36V
18V - 36V
18V - 36V
18V - 36V
18V - 36V
18V - 36V
3.3V - 30V
5V - 30V
IN
RANGE
V
1.25V
1.5V
1.8V
2.5V
3.3V
5V
1.25V
1.5V
1.8V
2.5V
3.3V
5V
1.25V
1.5V
1.8V
2.5V
3.3V
5V
1.25V
1.5V
1.8V
2.5V
3.3V
5V
–3.3V
–5V
OUT
C
2.2μF 50V 1206 X7R
2.2μF 50V 1206 X7R
2.2μF 50V 1206 X7R
2.2μF 50V 1206 X7R
2.2μF 50V 1206 X7R
2.2μF 50V 1206 X7R
2.2μF 16V 0805 X7R
2.2μF 16V 0805 X7R
2.2μF 16V 0805 X7R
2.2μF 16V 0805 X7R
2.2μF 16V 0805 X7R
2.2μF 16V 0805 X7R
1μF 25V 0805 X7R
1μF 25V 0805 X7R
1μF 25V 0805 X7R
1μF 25V 0805 X7R
1μF 25V 0805 X7R
4.7μF 25V 0805 X7R
2.2μF 50V 1206 X7R
2.2μF 50V 1206 X7R
2.2μF 50V 1206 X7R
2.2μF 50V 1206 X7R
2.2μF 50V 1206 X7R
2.2μF 50V 1206 X7R
2.2μF 50V 1206 X7R
2.2μF 50V 1206 X7R
IN
IN
than if the turn-on is
IN
is in the required
IN
or when
C
47μF 6.3V 1206 X5R
47μF 6.3V 1206 X5R
47μF 6.3V 1206 X5R
22μF 6.3V 1206 X7R
10μF 6.3V 1206 X7R
10μF 6.3V 1206 X7R
22μF 6.3V 1206 X7R
10μF 6.3V 0805 X7R
10μF 6.3V 0805 X7R
10μF 6.3V 0805 X7R
10μF 6.3V 0805 X7R
None
47μF 6.3V 0805 X5R
47μF 6.3V 0805 X7R
10μF 6.3V 0805 X7R
10μF 6.3V 0805 X7R
10μF 6.3V 0805 X7R
10μF 6.3V 0805 X5R
47μF 6.3V 1206 X5R
47μF 6.3V 1206 X5R
22μF 6.3V 1206 X7R
10μF 6.3V 0805 X7R
10μF 6.3V 0805 X7R
10μF 6.3V 0805 X7R
22μF 6.3V 0805 X7R
10μF 6.3V 0805 X7R
OUT
Electromagnetic Compliance
The LTM8020 was evaluated by an independent nationally
recognized test lab and found to be compliant with EN55022
class B: 2006 by a wide margin. A sample graph of the
LTM8020’s radiated EMC performance is given in the
Typical Performance Characteristics section, while further
data, operating conditions and test setup are detailed in
the electromagnetic compatibility test report, available
on the Linear Technology website. Conducted emissions
requirements may be met by adding an appropriate input
power line filter. The proper implementation of this filter
depends upon the system operating and performance
conditions as a whole, of which the LTM8020 is typically
only a component, so conducted emissions are not
addressed at this level.
R
Open
2.43M
1.1M
499k
301k
165k
Open
2.43M
1.1M
499k
301k
165k
Open
2.43M
1.1M
499k
301k
165k
Open
2.43M
1.1M
499k
301k
165k
301k
165k
ADJ
LTM8020
BIAS CONNECTION
>2V, < 25V
>2V, < 25V
>2V, < 25V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
>2V, <25V
>2V, <25V
>2V, <25V
V
V
V
V
V
OUT
OUT
OUT
IN
IN
IN
IN
OUT
OUT
IN
IN
IN
IN
OUT
OUT
OUT
OUT
OUT
OUT
OUT
11
8020fd