Richtek RT9526GE, RT9526GQW, RT9526GQWA Schematic [ru]

RT9526

Linear Single Cell Li-Ion Battery Charger with Input Over
Voltage Protection

General Description

The RT9526 is a fully integrated low cost single cell Li-ion

battery charger ideal for portable applications. The RT9526

is capable of being powered up from AC adapter and USB

(Universal Serial Bus) port inputs. The RT9526 enters

sleep mode when supplies are removed. The RT9526

optimizes the charging task by using a control algorithm

including preconditioning mode, fast charge mode, and

constant voltage mode. The charging task will remain in

constant voltage mode to hold the battery in a full charge

condition. The charge current can be programmed with an

external resistor. The internal thermal feedback circuitry

regulates the die temperature to optimize the charge rate

under all ambient temperatures. The RT9526 features 28V

maximum rating voltage for VIN. The other features are

under voltage protection and over voltage protection for

the AC adapter supply.

The RT9526 is available in WDFN-8L 2x2, WDFN-8L 2x3

and SOT-23-6 packages to achieve best solution for PCB

space and total BOM cost saving considerations.

Features

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z 28V Maximum Rating for AC Adapter

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z Internal Integrated Power FETs

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z AC Adapter Power Good Status Indicator

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z Programmed Charging Current

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z Charge Status Indicator

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z Programmed End of Charge Current

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z Under Voltage Protection

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z Over Voltage Protection

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z Thermal Feedback Optimizing Charge Rate

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z RoHS Compliant and Halogen Free

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Applications

z Cellular Phones

z Digital Cameras

z PDAs and Smart Phones

z Portable Instruments

Pin Configurations

(TOP VIEW)

Ordering Information

RT9526

Package Type
E : SOT-23-6
QW : WDFN-8L 2x2 (W-Type)
QWA : WDFN-8L 2x3 (W-Type)

Lead Plating System
G : Green (Halogen Free and Pb Free)

Note :

Richtek products are :

` RoHS compliant and compatible with the current require-

ments of IPC/JEDEC J-STD-020.

` Suitable for use in SnPb or Pb-free soldering processes.

IMIN

CHG_SB GND VIN

SOT-23-6

1

VIN

2

PGB

ENB

3

4

CHG_SB

WDFN-8L 2x2

1

VIN

2

PGB

ENB

3

4

CHG_SB

WDFN-8L 2x3

ISET BATT

4

56

23

8

BATT

7

ISET

6

GND9IMIN

5

GND

8

BATT

7

ISET

6

GND

IMIN

9

5

GND

DS9526-01 April 2011 www.richtek.com

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RT9526

Marking Information

RT9526GE RT9526GQW RT9526GQWA

EN= : Product Code

EX=DNN

DNN : Date Code

Typical Application Circuit

JJW 04W

JJ : Product Code

W : Date Code

04 : Product Code

W : Date Code

Adapter or USB

R

R

ISET

IMIN

VIN

C

IN

ISET

IMIN

GND

ENB

RT9526

CHG_SB

BATT

PGB

R1

R2

C

OUT

V

BATT

V

BATT

Function Pin Description

Pin No.

SOT-26-6

WDFN-8L 2x2 /

WDFN-8L 2x3

3 1 VIN Supply Voltag e Input. VIN can withstan d up to 28V input .

-- 2 PGB

1 3 CHG_SB

-- 4 ENB

2

9 (Exposed Pad)

5,

6 6 IMIN EOC Current Settin g Pin.

5 7 ISET Char ge Current Set Point.

4 8 BATT Battery Charge Curren t Output.

Pin Name Pin Function

Power Good Indicator. This pin connects to VIN with 10SL
N-MOSFET as power good c ondition.
Char ge Stat us Indicator Output (Open drain). Indicate low when
battery is charging; indicat e high when battery charging fini shed or
any fault happened.

Char ge En able (Active Lo w). Connect this pin with 2 00kΩ pull low
resistor.

GND

Ground. Th e exposed pad must be solde red to a large PCB and
conn ected to GND for maximum power dissipa tion.

DS9526-01 April 2011www.richtek.com

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Function Block Diagram

RT9526

Switch

Well

VIN

ISET

ENB

BASE

Sleep
Mode

Current

Set Block

OVP

UVLO

200k

V

REF

I

BIAS

CC/CV/TR
Multi Loop

Controller

Logic

EOC Set

Block

BATT

IMIN

CHG_SB

PGB

GND

DS9526-01 April 2011 www.richtek.com

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RT9526

Flow Chart

Standby State

P-MOSFET = OFF

NO

V

< UVLO &

IN

V

< OVP &

IN

ENB = L

Power Off State

P-MOSFET = OFF

Any State or

> OVP or

V

IN

> UVLO or

V

IN

ENB = H

YES

V

- V

BATT

> V

OS

IN

NO

Sleep State

P-MOSFET = OFF

YES YES

BATT > 2.8V Soft-Start

NO

Pre_Charge

I

CHG_PRE

I

CHG_FAST, HG_SB = L

= (1/6) x

CV State

V

I

CHG =

= 4.2V

BATT

0A CHG_SB

= H

YES

Figure 1. Operation State Diagram for Charger function

Fast-Charge

I

CHG_FAST

R

SET

CHG_SB = L

V

BATT

= 150mA

= 29.4k

8 4.2V

≥

NO

VIN > UVLO

< OVP &

& V

IN

V

IN-VBATT

> V

OS

Figure 2. PGB State

ENB = L CHG _SB = H

YES

I

< I

IMIN

> 2.8V

&

CHG

V

BATT

NO

YES

NO

CHG_SB = H

CHG_SB = L

YES

NO

PGB = L

PGB = H

I

CHG

& V

YES

NO

< I

CHG_FAST

BATT

< 2.8V

Figure 3. CHG_SB State

DS9526-01 April 2011www.richtek.com

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RT9526

Absolute Maximum Ratings (Note 1)

z Supply Voltage, VIN ------------------------------------------------------------------------------------------------------ −0.3V to 28V

z CHG_SB, PGB Pins ------------------------------------------------------------------------------------------------------ −0.3V to 7V

z Others ------------------------------------------------------------------------------------------------------------------------ −0.3V to 6V

z Power Dissipation, P

SOT-23-6 -------------------------------------------------------------------------------------------------------------------- 0.4W

WDFN-8L 2x2 -------------------------------------------------------------------------------------------------------------- 0.606W

WDFN-8L 2x3 -------------------------------------------------------------------------------------------------------------- 0.833W

z Package Thermal Resistance (Note 2)

SOT-23-6, θJA--------------------------------------------------------------------------------------------------------------- 250°C/W

WDFN-8L 2x2, θJA--------------------------------------------------------------------------------------------------------- 165°C/W

WDFN-8L 2x2, θJC--------------------------------------------------------------------------------------------------------- 8.2°C/W

WDFN-8L 2x3, θJA--------------------------------------------------------------------------------------------------------- 120°C/W

WDFN-8L 2x3, θJC--------------------------------------------------------------------------------------------------------- 8.2°C/W

z Lead Temperature (Soldering, 10 sec.)------------------------------------------------------------------------------- 260°C

z Junction Temperature ----------------------------------------------------------------------------------------------------- 150°C
z Storage Temperature Range -------------------------------------------------------------------------------------------- −65°C to 150°C

@ T

D

= 25°C

A

Recommended Operating Conditions (Note 3)

z Junction Temperature Range -------------------------------------------------------------------------------------------- −40°C to 125°C

z Ambient Temperature Range -------------------------------------------------------------------------------------------- −40°C to 85°C

Electrical Characteristics

(V

= 4.5V, T

IN

VIN POR Rising Threshold
Voltage

VIN POR Falling Threshold
Voltage

VIN − V

VIN − V

VIN Standby Current V

BATT Sleep Leakage Current I

Battery Regulation Voltage V

VIN Power FET On-Resistance R
ISET Set Voltage (Fast Charge

Phase)
Charge Current Accuracy R

BATT Pre-Charge Threshold V

BATT Pre-Charge Threshold
Hysteresis

Pre-Charge Current I

ENB Input
Threshold Voltage

= 25°C unless otherwise specified)

A

Parameter Symbol Test Conditions Min Typ Max Unit

3.4 3.8 4.2 V

POR_H

3.1 3.5 3.9 V

POR_H

-- 90 150 mV

OS_H

10 50 -- mV

POR_L

= 4.5V -- 300 500 μA

BATT

-- 1 5 μA

4.158 4.2 4.242 V

REG

I

DS(ON)

-- 1.21 -- V

ISET

CHG_PRE

CHG_PRE

2.7 2.8 2.9 V

40 100 150 mV

= 0.5A -- 0.6 -- Ω

BATT

= 29.4kΩ 135 150 165 mA

ISET

12 16.7 21.3 %

V

= 4.2V to 24V

IL

IN

-- -- 0.4

V

VOS Ris ing V

BATT

VOS Falling V

BATT

Logic-High VIH 1.5 -- --

Logic-Low V

V

V

SLEEP

V

ΔV

CHG_PRE

To be continued

DS9526-01 April 2011 www.richtek.com

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