Richtek RT9526AGE, RT9526AGQW Schematic [ru]

RT9526A

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

General Description

The RT9526A is a fully integrated low cost single cell Liion battery charger ideal for portable applications. The RT9526A is capa ble of being powered up from AC ada pter and USB (U niversal Serial Bus) port inputs. The RT9526A enters sleep mode when supplies are removed. The RT9526A opti mizes the charging task by using a control algorithm including preconditioning mode, fast charge mode, and consta nt voltage mode. The charging ta sk will remain in constant voltage mode to hold the battery in a full charge condition. The charge current can be programmed with a n external resistor . The internal thermal feedback circuitry regulates the die temperature to opti mize the charge rate under all ambient temperatures. The RT9526A features 28V maximum rating voltage for VIN. Under-voltage protection a nd over-voltage protection are provided for the AC a da pter supply.

The RT9526A is available in the WDFN-8L 2x3 and SOT-23-6 pa ckage to achieve be st solution for PCB space and total BOM cost saving considerations.

Applications

 Cellular Phones  Digital Camera s  PDAs and Smart Phones  Portable Instruments

Features



 28V Maximum Rating for AC Adapter with Over-



Voltage Protection 7V



 Internal Integrated Power FETs



 AC Adapter Power Good Status Indicator



 Programmed Charging Current



 Charge Status Indicator



 Programmed End of Charge Current



 Under-Voltage Protection



 Thermal Feedback Optimizing Charge Rate



 RoHS Compliant and Halogen Free



Ordering Information

RT9526A

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

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.

Simplified Application Circuit

Adapter or USB

ISET

IMIN

DS9526A-03 July 2014 www.richtek.com

VIN

ISET IMIN

GND

ENB

RT9526A

CHG_SB

BATT

PGB

OUT

BATT

RT9526A

Marking Information

RT9526AGQW

05 : Product Code

05W

RT9526AGE

0X=DNN

W : Date Code

0X= : Product Code DNN : Date Code

Function Pin Description

Pin No.

WDFN-8L 2x3 SO T-2 3- 6

1 3 VIN Supply Voltage Input. VIN can withstand up to 28V input. 2 -- PGB

3 1 CHG_SB

4 -- ENB

9 (Exp ose d Pad)

2 GND

6 6 IMIN EOC Current Setting. 7 5 ISET Charge Current Set Point. 8 4 BATT Battery Charge Current Output.

Pin Name Pin Fun ction

Pin Configurations

(TOP VIEW)

VIN

PGB

CHG_SB

3 4

ENB

WDFN-8L 2x3

IMIN

CHG_SB

SOT-23-6

Po wer Go od In dic ato r . This pin con nec ts to VIN with 10S L N-M O SFE T as power good condition.

Charge Status Indicator Output (Open-Drain). Indicate low when bat t ery is charging; indi c ate hi gh wh en ba tte r y char gi ng fi nish ed or an y fault happened.

Enable Control Input (Active Low). Connect this pin with a 200k pull-low resistor.

Ground. The exposed pad must be soldered to a large PCB and connected to GND for maximum power dissipation.

8 7 6

GND

ISET BATT

VIN

GND

BATT ISET IMIN GND

DS9526A-03 July 2014www.richtek.com

Function Block Diagram

RT9526A

Switch

Well

Operation

VIN

ISET

ENB

BASE

Sleep Mode

Current

Set Block

OVP

UVLO

200k

V I

BIAS

REF

CC/CV/TR Multi Loop

Controller

Logic

EOC Set

Block

BATT

IMIN

CHG_SB

PGB

GND

The RT9526A is a fully integrated low cost single cell Liion charger. It provides a fast-charge current setting by resistor R

. Pre-charge is 16.7% of fast charge current,

IREF

while VBAT < 2.45V. The PGB pin is low, while VIN > POR, VIN < OVP , and VIN − VBA T > V

. The CHG_SB

OSH_H

pin is low, while RT9526A is charging. The CHG_SB pin will go high while end of charger happen s. End of charge condition is set by R

. CHG_SB will go low again, while

IMIN

charge current is larger than 75% of fast-charge setting. The RT9526A charges continuously after end of charge happen s. Li-ion battery will be full charged until CV = 4.2V . The RT9526A ca n be disa bled by ENB = H.

DS9526A-03 July 2014 www.richtek.com

RT9526A

Absolute Maximum Ratings (Note 1)

 Supply V oltage, VIN ------------------------------------------------------------------------------------------------------ −0.3V to 28V  CHG_SB, PGB ------------------------------------------------------------------------------------------------------------ −0.3V to 7V  Other Pins------------------------------------------------------------------------------------------------------------------- −0.3V to 6V  Power Dissipation, P

WDFN-8L 2x3 -------------------------------------------------------------------------------------------------------------- 3.17W SOT-23-6 -------------------------------------------------------------------------------------------------------------------- 0.48W

 Package Thermal Re sistance (Note 2)

W DF N-8L 2x3, θJA--------------------------------------------------------------------------------------------------------- 31.5°C/W WDFN-8L 2x3, θJC--------------------------------------------------------------------------------------------------------- 7.5°C/W SOT-23-6, θJA--------------------------------------------------------------------------------------------------------------- 208.2°C/W

 Lead Temperature (Soldering, 10 sec.)------------------------------------------------------------------------------- 260°C  Junction T emperature----------------------------------------------------------------------------------------------------- 150°C  Storage T emperature Range -------------------------------------------------------------------------------------------- −65°C to 150°C

Recommended Operating Conditions (Note 3)

 Junction T emperature Range-------------------------------------------------------------------------------------------- −40°C to 125°C  Ambient T emperature Range-------------------------------------------------------------------------------------------- −40°C to 85°C

@ T

= 25°C

Electrical Characteristics

= 4.5V, T

VI N POR Ri si ng Thresh old

Voltage

VIN POR Falling Threshold

Voltage

VIN  V VIN  V VI N Standby Cur rent V BATT Sleep Leakage Current I Battery Regulation Voltage V VIN Power M OSFET

On-Resistance

IS ET Set Volta ge

(Fast Charge Phase)

Cha r ge Cur ren t Acc urac y R BATT Pre- Cha r ge Thr es hol d V BATT Pre- Cha r ge Thr es hol d

Hysteresis

Pre-Charge Current I ENB Input

T hres hol d Vol tag e

Th erm al R egu lati on T

= 25°C unless otherwise specified)

Parameter Symbol Test Conditions Min Typ Max Unit

VOS Rising V

BATT

VOS Fa llin g V

BATT

Logic-High V

SLEEP

V

CHG_PRE

3.4 3.8 4.2 V

POR_H

3.1 3.5 3.9 V

POR_L

-- 90 150 mV

OS_H

10 50 -- mV

OS_L

-- 1 5 A

4.158 4.2 4.242 V

REG

DS(ON)

-- 1.22 -- V

ISET

CHG_PRE

2.45 2.55 2.65 V 40 100 150 mV

12 16.7 21.3 %

Logic-Low VIL -- -- 0.4

-- 115 -- C

REG

= 4.5V -- 400 600 A

BATT

= 0.5A -- 0.6 -- 

BATT

= 24.3k  450 500 550 mA

ISET

= 4.2V to 24V

1.5 -- -V

DS9526A-03 July 2014www.richtek.com

RT9526A

Parameter Symbol Test Conditions Min Typ Max Unit

VIN Over-Voltage Protection Threshold

VIN OVP Hysteresis V PGB Pull-Down Voltage 5mA -- 200 -- mV CHG_SB Pull-Down Voltage 5mA -- 200 -- mV EOC Current Setting I EOC Rising Threshold R

Note 1. Stresses beyond those listed “Absolute Maximum Ratings” may cause permanent damage to the device. These are

stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions may affect device reliability.

Note 2. θ

Note 3. The device is not guaranteed to function outside its operating conditions.

is measured at T

measured at the exposed pad of the package.

6.7 7 7.5 V

OVP

-- 0.1 -- V

OVP

IMIN

= 25°C on a high effective thermal conductivity four-layer test board per JEDEC 51-7. θJC is

= 243k -- 45 -- mA

IMIN

= 24.3k 337.5 375 412.5 mA

IREF

DS9526A-03 July 2014 www.richtek.com

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