CS5207-1GT3 ON Semiconductor, CS5207-1GT3 Datasheet - Page 5

• Manufacturer Part Number: CS5207-1GT3
• Description: IC REG LINEAR ADJ OUT 7A TO220AB
• Manufacturer: ON Semiconductor

Specifications of CS5207-1GT3

• Regulator Topology: Positive Adjustable
• Voltage - Output: 1.25 ~ 13 V
• Voltage - Input: Up to 17V
• Voltage - Dropout (typical): 1.4V @ 7A
• Number Of Regulators: 1
• Current - Output: 7A
• Current - Limit (min): 7.1A
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Through Hole
• Package / Case: TO-220-3 (Straight Leads)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: CS5207-1GT3OS

Output Voltage Sensing
possible to provide true remote load sensing. Load
regulation is limited by the resistance of the conductors
connecting the regulator to the load.
to the output pin of the regulator as shown in Figure 9. If R1
is connected to the load, R
and the effective resistance between the regulator and the
load becomes.
where R
V
Calculating Power Dissipation and Heat Sink
Requirements
shutdown and safe operating area circuitry to protect the
device. High power regulators such as these usually operate
at high junction temperatures so it is important to calculate
the power dissipation and junction temperatures accurately
to ensure that an adequate heat sink is used.
electrical isolation may be required for some applications.
Thermal compound should always be used with high current
regulators such as these.
following four factors:
1. Maximum Ambient Temperature T
2. Power dissipation P
3. Maximum junction temperature T
4. Thermal resistance junction to ambient R
IN
Figure 9. Grounding Scheme for Adjustable Output
Since the CS5207−1 is a three terminal regulator, it is not
Best load regulation occurs when R1 is connected directly
Regulator to Minimize Parasitic Resistance Effects
The CS5207−1 linear regulator includes thermal
The case is connected to V
The thermal characteristics of an IC depend on the
These four are related by the equation
C
= conductor parasitic resistance.
V
IN
CS5207−1
Adj
T J + T A ) P D
R C
V
OUT
D
C
(Watts)
is multiplied by the divider ratio
R1 ) R2
R1
R
R
OUT
1
2
R QJA
R
C
J
on the CS5207−1,
A
(°C)
Conductor Parasitic
(°C)
Resistance
ΘJA
(°C/W)
http://onsemi.com
R
LOAD
(1)
5
dissipation are determined by the design while the
maximum junction temperature and the thermal resistance
depend on the manufacturer and the package type.
P D(max) + { V IN(max) * V OUT(min) } I OUT(max) ) V IN(max) I Q
where:
package to improve the flow of heat away from the IC and
into the surrounding air.
outside environment has a thermal resistance. Like series
electrical resistances, these resistances are summed to
determine R
junction and the surrounding air.
1. Thermal Resistance of the junction to case, R
2. Thermal Resistance of the case to Heat Sink, R
3. Thermal Resistance of the Heat Sink to the ambient
the result can be substituted in equation (1).
for a given package type based on average die size. For a
high current regulator such as the CS5207−1 the majority of
the heat is generated in the power transistor section. The
value for R
depends on factors such as package type, heat sink interface
(is an insulator and thermal grease used?), and the contact
area between the heat sink and the package. Once these
calculations are complete, the maximum permissible value
of R
For further discussion on heat sink selection, see application
note
AND8036/D, available through the Literature Distribution
Center or via our website at http://onsemi.com.
The maximum ambient temperature and the power
The maximum power dissipation for a regulator is:
V
V
I
I
A heat sink effectively increases the surface area of the
Each material in the heat flow path between the IC and the
These are connected by the equation:
The value for R
The value for R
OUT(max)
Q
IN(max)
OUT(min)
ΘJA
application
(°C/W)
(°C/W)
air, R
is the maximum quiescent current at I
“Thermal
can be calculated and the proper heat sink selected.
ΘSA
ΘSA
R QJA + R QJC ) R QCS ) R QSA
is the maximum input voltage,
ΘJA
is the minimum output voltage,
is the maximum output current, for the
(°C/W)
depends on the heat sink type, while R
, the total thermal resistance between the
ΘJC
ΘJA
Management,”
is normally quoted as a single figure
is calculated using equation (3) and
document
OUT(max)
ΘJC
number
ΘCS
.
ΘCS
(2)
(3)