MCP1631RD-MCC2 Microchip Technology, MCP1631RD-MCC2 Datasheet - Page 14

• Manufacturer Part Number: MCP1631RD-MCC2
• Description: REFERENCE DESIGN MCP1631HV
• Manufacturer: Microchip Technology

Specifications of MCP1631RD-MCC2

• Main Purpose: Power Management, Battery Charger
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: MCP1631HV, PIC16F883
• Primary Attributes: 1 ~ 2 Cell- Li-Ion, 1 ~ 5 Cell- NiCd/NiMH, 1 ~ 2 1W LEDs
• Secondary Attributes: Status LEDs
• Silicon Manufacturer: Microchip
• Application Sub Type: Battery Charger
• Kit Application Type: Power Management - Battery
• Silicon Core Number: MCP1631HV, PIC16F883
• Kit Contents: Board
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

AN1137
Q
Inductor slope’s must me equal for volt-time balance:
Multiply both sides by 1/(t
Solving for V
Set V
Boost stage:
Solving for V
Looking back, if D/(1-D) x V
is shown that V
enough that the ripple voltage on C
Now that the duty cycle is known as a V
relationship, the duty cycle can be calculated for any
input output condition. Remember, this transfer
function is dependent upon the fact that inductor
current is continuous or never reached zero. If it does
reach zero, this transfer function is no longer true and
there is another state added to the operation.
DS01137A-page 14
1
V
Turned off (- Slope):
C1
C1
=
= V
V
IN
C1
V
t
C1
OUT
ON
×
C1
V
.
for both the Boost stage and the Buck-
⎛
⎝
C1
------------ -
1 D
C1
/V
×
×
V
-------------
–
1
V
ΔI
------------
V
--------- -
L
D
IN:
t
OUT
=
OFF
= V
W2
IN
C1
W2
=
⎞
⎠
V
OUT
–
=
V
IN
=
=
V
OUT
ON
. This is true, if C
t
OUT
⎛
⎝
OFF
V
-------------
×
------------ -
1 D
IN
L
OUT
+ t
W2
D
–
⎛
⎝
×
is substituted for V
1 D
------------ -
×
=
OFF
(
–
D
1 D
⎞
⎠
V
-------------
L
V
–
OUT
W2
):
OUT
1
⎞
⎠
is low.
)
×
⎛
⎝
1 D
------------ -
–
D
1
OUT
is large
⎞
⎠
OUT
/V
, it
IN
© 2007 Microchip Technology Inc.