MICROCHIP MCP73826 Technical data

M

MCP73826

Single Cell Lithium-Ion Charge Management Controller

Features

• Linear Charge Management Controller for Single
Lithium-Ion Cells

• High Accuracy Preset Voltage Regulation:

+

1% (max)

• Two Preset Voltage Regulation Options:

- 4.1V - MCP73826-4.1

- 4.2V - MCP73826-4.2

• Programmable Charge Current

• Automatic Cell Preconditioning of Deeply
Depleted Cells, Minimizing Heat Dissipation Dur­ing Initial Charge Cycle

• Automatic Power-Down when Input Power
Removed

• Temperature Range: -20°C to +85°C

• Packaging: 6-Pin SOT-23A

Applications

• Single Cell Lithium-Ion Battery Chargers

• Personal Data Assistants

• Cellular Telephones

• Hand Held Instruments

• Cradle Chargers

• Digital Cameras

Typical Application Circuit

500 mA Lithium-Ion Batt ery Charger

V

IN

5V

MA2Q705

10 µF

100 k

100 m

Ω

NDS8434

Ω

4

6

V

V

DRV

SNS

5

V

IN

12

SHDN

MCP73826

V

GND

BAT

3

10 µF

+

Single
Lithium-Ion

-

Cell

Description

The MCP73826 is a linear charge management con­troller for use in space-limited, cost sensitive applica­tions. The MCP73826 combines high accuracy
constant voltage, controlled current regulation, and cell
preconditioning in a space saving 6-pin SOT-23A pack­age. The MCP73826 provides a stand-alone charge
management solution.

The MCP73826 charges the battery in three phases:
preconditioning, controlled current, and constant volt­age. If the battery voltage is below the internal low-volt­age threshold, the battery is preconditioned with a
foldback current. The preconditioning phase protects
the lithium-ion cell and minimizes heat dissipation.

Following the preconditioning phase, the MCP73826
enters the controlled current phase. The MCP73826
allows for design flexibility with a programmable charge
current set by an external sense resistor. The charge
current is ramped up, based on the cell voltage, from
the foldback current to the peak charge current estab­lished by the sense resistor. This phase is maintained
until the battery reaches the charge-regulation voltage.

Then, the MCP73826 enters the final phase, constant
voltage. The accuracy of the voltage regulation is better
than ±1% over the entire operating temperature range
and supply voltage range. The MCP73826-4.1 is preset
to a regulation voltage of 4.1V, while the MCP73826-

4.2 is preset to 4.2V.

The MCP73826 operates with an input voltage range
from 4.5V to 5.5V. The MCP73826 is fully specified
over the ambient temperature range of -20°C to +85°C.

Package Type

6-Pin SOT-23A

SHDN

GND

V

BAT

1

2

3

MCP73826

V

6

SNS

V

5

IN

V

4

DRV

 2002 Microchip Technology Inc. DS21705A-page 1

MCP73826

Functional Block Diagram

DRV

V

IN

V

BAT

V

(NOTE 1)

352.5 kΩ

REF

V

+

–

+

75 kΩ

–

AMPLIFIER

VOLTAGE CONTROL

CHARGE CURRENT

CONTROL AMPLIFIER

GND

75 kΩ

500 kΩ

12 kΩ

(1.2V)

REF

V

CHARGE

CURRENT

AMPLIFIER

–

+

1.1 kΩ

IN

V

SNS

V

IN

V

SHUTDOWN,

REFERENCE

GENERATOR

112 .5 kΩ

REF

V

SHDN

0.3V CLAMP

+

–

CHARGE CURRENT

FOLDBACK AMPLIFIER

37.5 kΩ

NOTE 1: Value = 340.5KΩ for MCP73826-4.1

Value = 352.5KΩ for MCP73826-4.2

DS21705A-page 2  2002 Microchip Technology Inc.

MCP73826

1.0 ELECTRICAL

PIN FUNCTION TABLE

CHARACTERISTICS

Pin Name Description

1.1 Maximum Ratings*

VIN ................................................................................... -0.3V to 6.0V

All inputs and outputs w.r.t. GND ................-0.3 to (VIN+0.3)V

Current at V

Maximum Junction Temperature, T

Storage temperature .....................................-65°C to +150°C

ESD protection on all pins..................................................≥ 4kV

*Notice: Stresses above those listed under “Maximum Ratings” may
cause permanent damage to the device. This is a stress rating only and
functional operation of the device at those or any other conditions
above those indicated in the operational listings of this specification is
not implied. Exposure to maximum rating conditions for extended peri­ods may affect device reliability.

.......................................................... +/-1 mA

DRV

.............................. 150°C

J

1 SHDN Logic Shutdown

2 GND Battery Management

0V Reference

3

4V

5V

V

BAT

DRV

IN

Cell Voltage Monitor Input

Drive Output

Battery Management
Input Supply

6V

SNS

Charge Current Sense Input

DC CHARACTERISTICS: MCP73826-4.1, MCP73826-4.2

Unless otherwise specified, all limits apply for VIN = [V
Typical values are at +25°C. Refer to Figure 1-1 for test circuit.

Parameter Sym Min Typ Max Units Conditions

Supply Voltage V

Supply Current I

Voltage Regulation (Constant Voltage Mode)

Regulated Output Voltage V

Line Regulation ∆V

Load Regulation ∆V

Output Reverse Leakage Current I

External MOSFET Gate Drive

Gate Drive Current I

Gate Drive Minimum Voltage V

Current Regulation (Controlled Current Mode)

Current Sense Gain A

Current Limit Threshold V

Foldback Current Scale Factor K — 0.43 — A/A

Shutdown Input - SHDN

Input High Voltage Level V

Input Low Voltage Level V

Input Leakage Current I

REG

IN

IN

REG

BAT

BAT

LK

DRV

DRV

CS

CS

IH

IL

LK

(typ)+1V], R

4.5

—
—

4.059

4.158

SENSE

—

0.5

260

4.1

4.2

= 500 mΩ, T

5.5 V

15

560

4.141

4.242

= -20°C to +85°C.

A

-10 — 10 mV VIN = 4.5V to 5.5V,

-1 +0.2 1 mV I

—8—µAV

—

0.08

—
—

1

—

—1.6— V

—100— dB∆(V

40 53 75 mV (VIN-V

40 — — %V

——25%V

—— 1 µAV

µA Shutdown, V

Constant Voltage Mode

V

MCP73826-4.1 only

V

MCP73826-4.2 only

I

OUT

OUT

=Floating, V

IN

SHDN

= 75 mA

= 10 mA to 75 mA

mAmASink, CV Mode

Source, CV Mode

SNS-VDRV

) at I

SNS

IN

IN

= 0V to 5.5V

SHDN

= 0V

BAT=VREG

) / ∆V

BAT

OUT

TEMPERATURE SPECIFICATIONS

Unless otherwise specified, all limits apply for VIN = 4.5V-5.5V

Parameters Sym Min Typ Max Units Conditions

Temperature Ranges

Specified Temperature Range T

Operating Temperature Range T

Storage Temperature Range T

A

A

A

Thermal Package Resistances

Thermal Resistance, 6-Pin SOT-23A θ

 2002 Microchip Technology Inc. DS21705A-page 3

JA

-20 — +85 °C

-40 — +125 °C

-65 — +150 °C

—230— °C/W

4-Layer JC51-7 Standard
Board, Natural Convection

MCP73826

VIN = 5.1V

(MCP73826-4.1)

= 5.2V

V

IN

(MCP73826-4.2)

22 µF

FIGURE 1-1: MCP73826 Test Circuit.

100 k Ω

R

SENSE

5

1

6

V

SNS

V

IN

SHDN

MCP73826

NDS8434

4

V

DRV

V

GND

BAT

I

OUT

V

OUT

3

2

22 µF

DS21705A-page 4  2002 Microchip Technology Inc.

MCP73826

2.0 TYPICAL PERFORMANCE CHARACTERISTICS

Note: The graphs and tables provided following this note are a statistical summary based on a limited number of

samples and are provided for informational purposes only. The performance characteristics listed herein
are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified
operating range (e.g., outside specified power supply range) and therefore outside the warranted range.

Note: Unless otherwise indicated, I

= 10 mA, Constant Voltage Mode, TA = 25°C. Refer to Figure 1-1 for test circuit.

OUT

FIGURE 2-1: Output Voltage vs. Output Current (MCP73826-4.2).

FIGURE 2-2: Output Voltage vs. Input Voltage (MCP73826-4.2).

FIGURE 2-4: Supply Current vs. Output Current.

FIGURE 2-5: Supply Current vs. Input Voltage.

FIGURE 2-3: Output Voltage vs. Input Voltage

(MCP73826-4.2).

 2002 Microchip Technology Inc. DS21705A-page 5

FIGURE 2-6: Supply Current vs. Input Voltage.

MCP73826

Note: Unless otherwise indicated, I

FIGURE 2-7: Output Reverse Leakage Current vs. Output Voltage.

= 10 mA, Constant Voltage Mode, TA = 25°C. Refer to Figure 1-1 for test circuit.

OUT

FIGURE 2-10: Supply Current vs. Temperature.

FIGURE 2-8: Output Reverse Leakage Current vs.

Output Voltage.

FIGURE 2-9: Current Limit Foldback.

FIGURE 2-11: Output Voltage vs. Temperature

(MCP73826-4.2).

FIGURE 2-12: Power-Up / Power-Down.

DS21705A-page 6  2002 Microchip Technology Inc.

MCP73826

Note: Unless otherwise indicated, I

FIGURE 2-13: Line Transient Response.

= 10 mA, Constant Voltage Mode, TA = 25°C. Refer to Figure 1-1 for test circuit.

OUT

FIGURE 2-15: Load Transient Response.

FIGURE 2-14: Line Transient Response.

FIGURE 2-16: Load Transient Response.

 2002 Microchip Technology Inc. DS21705A-page 7

MCP73826

3.0 PIN DESCRIPTION

The descriptions of the pins are listed in Table 3-1.

Pin Name Description

1 SHDN Logic Shutdown

2 GND Battery Management

0V Reference

3

4V

5V

6V

TABLE 3-1: Pin Function Table.

V

BAT

DRV

IN

SNS

3.1 Logic Shutdown (SHDN)

Input to force charge termination, initiate charge, or ini­tiate recharge.

3.2 Battery Management 0V Reference (GND)

Connect to negative terminal of battery.

Cell Voltage Monitor Input

Drive Output

Battery Management
Input Supply

Charge Current Sense Input

3.4 Drive Output (V

Direct output drive of an external P-channel MOSFET
pass transistor for current and voltage regulation.

DRV

)

3.5 Battery Management Input Supply (VIN)

A supply voltage of 4.5V to 5.5V is recommended.
Bypass to GND with a minimum of 10 µF.

3.6 Charge Current Sense Input (V

Charge current is sensed via the voltage developed
across an external precision sense resistor. The sense
resistor must be placed between the supply voltage
(V

) and the source of the external pass transistor. A

IN

50 mΩ sense resistor produces a fast charge current of

1A, typically.

SNS

)

3.3 Cell Voltage Monitor Input (V

Voltage sense input. Connect to positive terminal of
battery. Bypass to GND with a minimum of 10 µF to
ensure loop stability when the battery is disconnected.
A precision internal resistor divider regulates the final
voltage on this pin to V

REG

.

BAT

)

DS21705A-page 8  2002 Microchip Technology Inc.