KIT34673EPEVBE Freescale Semiconductor, KIT34673EPEVBE Datasheet - Page 5

• Manufacturer Part Number: KIT34673EPEVBE
• Description: KIT EVALUATION FOR MC34673
• Manufacturer: Freescale Semiconductor
• Type: Battery Managementr

Specifications of KIT34673EPEVBE

• Main Purpose: Power Management, Battery Charger
• Embedded: No
• Utilized Ic / Part: MC34673
• Primary Attributes: 1 Cell- Li-Ion
• Secondary Attributes: LED Status Indicators
• Input Voltage: 2.6 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Product: Power Management Modules
• Supply Current: 1.2 A
• Silicon Manufacturer: Freescale
• Silicon Core Number: MC34673
• Kit Application Type: Power Management - Battery
• Application Sub Type: Battery Charger
• Kit Contents: Evaluation Board, CD
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: MC34673

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5.1
The input capacitor is used to minimize the input voltage transient that may cause instability. A
1.0µF or above ceramic capacitor 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 MC34673 is 28V, the input capacitor must
have 16V DC rated voltage.
5.2
The output capacitor is used for stable operation. A minimum of a 2.2µF ceramic capacitor is
required. On the evaluation board, a C2 of 2.2µF is necessary. The large capacitors of C4, C5,
and C6 are used to simulate the situation in the cell phone application where big capacitance is
put in parallel with the Li-ion battery. The user may remove C4, C5 and C6 if their system doesn’t
need such large capacitance. C4, C5, and C6 do not affect the performance of the MC34673.
Because the highest output voltage of the MC34673 is 4.2V, a 6.3V DC rated voltage is high
enough for the output capacitors.
5.3
The resistor between the ISET pin and GND sets the charge current by the following equation:
I
where R
should be used for 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.
different settings of the pin header JP7 and JP8.
Freescale Semiconductor
CHG
= 4000 / (R
Component Selection
ISET
Input capacitor C1
Output capacitors C2, C4, C5 and C6
Charge current setting resistors R6, R7 and R8
is in units of Ω, I
ISET
Using the High Input Voltage Charger for Single Cell Li-Ion
+96) (A)
Open
Short
Open
Short
CHG
Table 2. The Charge Current Settings
JP7
is in units of amps. A metal film with a 1% tolerance resistor
Open
Open
Short
Short
JP8
Table 2
300mA
600mA
900mA
1200mA
Charge Current
shows charge current with the
Batteries, Rev. 1.0
Component Selection
5