mc34063a-s08-t Unisonic Technologies, mc34063a-s08-t Datasheet - Page 10

• Manufacturer Part Number: mc34063a-s08-t
• Description: Variable Frequency Dc-dc Converter Controller Ic For Step-up Or Step-down Voltage Converter
• Manufacturer: Unisonic Technologies

MC34063A
V
V
The following power supply characteristics must be chosen:
V
V
I
F
V
OUT
MIN
CE(SAT)
F
IN
OUT
RIPPLE(P-P)
UTC assumes no responsibility for equipment failures that result from using products at values that
exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or
other parameters) listed in products specifications of any and all UTC products described or contained
herein. UTC products are not designed for use in life support appliances, devices or systems where
malfunction of these products can be reasonably expected to result in personal injury. Reproduction in
whole or in part is prohibited without the prior written consent of the copyright owner. The information
presented in this document does not form part of any quotation or contract, is believed to be accurate
and reliable and may be changed without notice.
(t
C
I
R
L(MIN)
C
SW
CALCULATION
ON
T
S
O
t
t
OFF
ON
+t
DESIGN FORMULA TABLE
OFF
)
MAX
UNISONIC TECHNOLOGIES CO., LTD
www.unisonic.com.tw
- Nominal input voltage.
- Desired output voltage,
- Desired output current.
- Saturation voltage of the output switch.
- Forward voltage drop of the ringback rectifier.
- Minimum desired output switching frequency at the selected values for V
- Desired peak-to-peak output ripple voltage. In practice, the calculated value will need to be increased
due to the capacitor equivalent series resistance and board layout. The ripple voltage should be kept
to a low value since it will directly effect the line and load regulation.
V
OUT
(
= 1.25 (1+R2/R1)
V
IN(MIN)
V
IN(MIN)
STEP-DOWN
- V
I
SW
8V
4x10
2I
I
V
CE(SAT)
SW
0.3/I
- V
OUT
RIPPLE(P-P)
OUT(MAX)
(t
F
ON
MIN
CE(SAT)
1
-5
+ V
+t
SW
- V
t
OFF
ON
F
OUT
- V
)
OUT
) t
ON(MAX)
(
V
2I
IN(MIN)
OUT(MAX)
V
V
OUT
IN(MIN)
I
STEP-UP
4x10
SW
V
- V
+ V
0.3/I
RIPPLE(P-P)
I
OUT
F
CE(SAT)
- V
MIN
1
F
t
-5
ON
- V
SW
t
CE(SAT)
t
t
ON
OFF
ON
+
IN(MIN)
LINEAR INTEGRATED CIRCUIT
t
) t
OFF
ON(MAX)
(
VOLTAGE-INVERTING
IN
V
2I
IN(MIN)
and I
OUT(MAX)
V
V
I
4x10
SW
V
IN
- V
OUT
OUT
0.3/I
RIPPLE(P-P)
I
- V
OUT
F
CE(SAT)
.
MIN
1
t
-5
CE(SAT)
ON
+ V
SW
t
t
t
ON
ON
OFF
+
F
t
) t
OFF
QW-R103-008,G
ON(MAX)
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