KIT34676EPEVBE Freescale Semiconductor, KIT34676EPEVBE Datasheet - Page 4

• Manufacturer Part Number: KIT34676EPEVBE
• Description: KIT EVALUATION FOR MC34676
• Manufacturer: Freescale Semiconductor
• Type: Battery Managementr

Specifications of KIT34676EPEVBE

• Main Purpose: Power Management, Battery Charger
• Embedded: No
• Utilized Ic / Part: MC34676
• Primary Attributes: 1 Cell- Li-Ion
• Secondary Attributes: Voltage input up to 28V
• Interface Type: USB
• Product: Power Management Modules
• Silicon Manufacturer: Freescale
• Silicon Core Number: MC34676
• Kit Application Type: Power Management - Battery
• Application Sub Type: Battery Charger
• Kit Contents: Board, CD
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: MC34676

Component Selection
5
5.1
5.2
5.3
5.4
4
Component Selection
Input capacitors C1 and C3
The input capacitor is used to minimize the input voltage transient that may cause instability. A ceramic capacitor of
1.0μF or above is required for most applications. X5R and X7R dielectrics have better temperature stability. The
evaluation board uses 1.0μF X5R ceramic capacitors. Considering the maximum input voltage rating of the MC34676B
is 28V, the input capacitor must have 16V DC rated voltage.
Output capacitors C4 and C5
The charger output capacitor is used for stable operation. An X5R ceramic capacitor minimum of a 1.0μF is required for
the charger output. Depending on the load transient current, a larger capacitance may be required. Because the highest
output voltage of the MC34676B is 4.2V, a 6.3V DC rated voltage is high enough for the output capacitor.
The regulator output capacitor is used for stable operation, too. An X5R ceramic capacitor minimum of a 1.0μF is
required for the regulator output. A 6.3V DC rated voltage is high enough for the regulator output capacitor because the
highest output voltage of the output regulator is 5V.
AC CC-mode charge current setting resistors R1, R2, and R3
The resistor between the ISET pin and GND sets the AC CC-mode charge current by the following equation:
where R
temperature stability. As a result, the charge current will be accurate over the whole temperature range.
On the evaluation board, three resistors with two pin header jumpers are used for the user to conveniently configure
different charge current values.
USB CC-mode charge current setting resistors R8 and R9
The resistor between the IUSB pin and GND sets the USB CC-mode charge current by the following equation:
where R
temperature stability. As a result, the charge current will be accurate over the whole temperature range.
On the evaluation board, two resistors with two pin header jumpers are used for the user to conveniently configure
different charge current values.
ISET
USB
is in units of Ω, I
is in units of Ω, I
Using the Dual 28V Input Voltage Charger with Linear Regulator,
Table 2. The USB CC-mode Charge Current Settings
Table 1. The AC CC-mode Charge Current Settings
USB
AC
Table 2
Table 1
is in units of amps. A metal film with a 1% tolerance resistor should be used for
is in units of amps. A metal film with a 1% tolerance resistor should be used for
Open
Open
Short
Short
J10
J6
shows the charge current with the different settings of pin headers J10 and J11.
shows the charge current with the different settings of pin headers J6 and J7.
I
I
USB
AC
=
=
------------- -
R
3950
------------- -
R
1975
ISET
IUSB
Open
Open
Short
Short
J11
J7
Charge Current
Charge Current
1050mA
150mA
450mA
750mA
Rev. 1.0
Freescale Semiconductor
Eqn. 1
Eqn. 2