MCP73113 datasheet(21/34 Pages) MICROCHIP

21 / 34 page

DS22183C-page 21

MCP73113/4

6.0

APPLICATIONS

The MCP73113/4 devices are designed to operate in

conjunction

with

host

microcontroller

standalone applications. The MCP73113/4 provides

the preferred charge algorithm for Lithium-Ion and

Lithium-Polymer cells Constant-current followed by

Constant-voltage.

Figure 6-1

depicts

typical

standalone

application

circuit,

while

Figure 6-2

depicts the accompanying charge profile.

FIGURE 6-1:

Typical Application Circuit.

FIGURE 6-2:

Typical Charge Profile

(875 mAh Battery).

6.1

Application Circuit Design

Due to the low efficiency of linear charging, the most

important factors are thermal design and cost, which

are a direct function of the input voltage, output current

and thermal impedance between the battery charger

and the ambient cooling air. The worst-case situation is

when

the

device

has

transitioned

from

the

Preconditioning mode to the Constant-current mode. In

this situation, the battery charger has to dissipate the

maximum power. A trade-off must be made between

the charge current, cost and thermal requirements of

the charger.

6.1.1

COMPONENT SELECTION

Selection of the external components in Figure 6-1 is

crucial to the integrity and reliability of the charging

system. The following discussion is intended as a guide

for the component selection process.

6.1.1.1

Charge Current

The preferred fast charge current for Li-Ion / Li-Poly

cells is below the 1C rate, with an absolute maximum

current at the 2C rate.

The recommended fast charge

current

should

obtained

from

battery

manufacturer. For example, a 500 mAh battery pack

with 0.7C preferred fast charge current has a charge

current of 350 mA. Charging at this rate provides the

shortest charge cycle times without degradation to the

battery pack performance or life.

–

STAT

VDD

PROG

VBAT

1-Cell

Ac-dc Adapter

VDD

VSS

RLED

CIN

COUT

VBAT

RPROG

Li-Ion

Battery

MCP73113/4 Typical Application

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

304560

7590

105 120

Time (Minutes)

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

RPROG = 2 kΩ

875 mAh Battery

Note:

Please consult with your battery supplier

or refer to battery data sheet for preferred

charge rate.

MCP73113 数据表(PDF) 21 Page - Microchip Technology

MCP73113 数据表(HTML) 21 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34

数据表下载