RICHTEK RT9541BCER, RT9541CCE, RT9541CCER, RT9541DCE, RT9541DCER Datasheet

Preliminary

RT9541

Li-Ion Battery Protector

General Description

The RT9541 Series are protection ICs for overcharge/discharge of rechargeable one-cell Lithium-ion (Li+) batteries by CMOS process.

The RT9541 Series can detect over-charge/discharge of Li+ one-cell and excess load current and charge current, further include a short circuit protector for preventing large external short circuit current.

Each of these ICs is composed of four voltage detectors, a reference unit, a hysteresis circuit, and a bidirectional short circuit protector. Package of SOT26 is available.

Features

zLow supply current

−Supply current: TYP. 2.0 A

−Standby current (after detecting overdischarge): Less than 0.2 A

zHigh accuracy detector threshold

−Over-charge detector: ±25mV

−Over-discharge detector: ±2.5%

zBuilt-in protection circuit

−Excess current trip/Short circuit protector in both charging and discharging direction

zOutput delay of over-charge adjustable with an external capacitor: 75mS at 0.01 F

zUltra small package: SOT26

Ordering Information

RT9541

Package type

E : SOT-26 Type I

ER : SOT-26 Type II

Operating temperature range

C: Commercial standard

See Table 1

Typical Application Circuit

R1			+
100Ω
C1		VDD
0.1µF
	CT	RT9541	V-
C3
0.01µF	VSS	DOUT	COUT

	C2	R2
		1KΩ
	0.1µF

Applications

zOver-charge / Over-discharge Protection for Li+ One-cell Pack

zHigh Precision Protectors for Cellular Phones or Instruments Using Li+ One-cell Battery

Pin Configurations

Part Number				Pin Configurations
RT9541 CE										TOP VIEW
										1.	COUT
(Plastic SOT-26)			6			5		4
										2.	CT
										3.	VSS
										4.	DOUT
			1			2		3
										5.	VDD
										6.	V-
RT9541 CER										TOP VIEW
(Plastic SOT-26)										1. DOUT
				6		5		4
										2.	V-
										3.	COUT
										4.	CT
				1		2		3
										5.	VDD
										6.	VSS

DS9541-05 August 2001	www.richtek-ic.com.tw
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RT9541		Preliminary
Absolute Maximum Ratings
z	Allowable Battery Voltage	-0.3V ~ 7V
z	Input Voltage (V)	VDD-14V to VDD +0.3V
z	Input Voltage (CT)	VSS-0.3V to VDD +0.3V
z	Output Voltage (COUT)	VDD-14V to VDD +0.3V

zOutput Voltage (DOUT) VSS-0.3V to VDD +0.3V

zPower Dissipation, PD @ TA = 25°C

SOT-26 0.25W

zPackage Thermal Resistance

SOT-26, θJA250°C/W

zOperating Temperature Range -20°C ~ +85°C

z Storage Temperature Range -65°C ~ +150°C

Electrical Characteristics

	Parameter	Symbol	Test Conditions	Min	Typ	Max	Units
	Operating Input Voltage	VDD	Voltage defined as VDD-VSS	1	--	6	V
	Charger Voltage	VCHG	Voltage defined as VDD-V-	--	--	14	V
	Minimum Operating Voltage for 0V		Voltage defined as VDD-V-	--	--	1	V
	Charging		VDD-VSS = 0V
	Accuracy of Over-charge	∆VOCHG	Detect rising edge of supply	-25	--	25	mV
	Threshold Voltage		voltage
	Over-charge Threshold Hysteresis			0.1	0.15	0.2	V
	Output Delay Time of Over-charge	TOCHG	C3 = 0.01µF, VDD = 3.6V ~	30	60	80	mS
			4.3V
	Accuracy of Over-discharge	∆VODISCHG	Detect falling edge of supply	-2.5	--	2.5	%
	Threshold Voltage		voltage
	Output Delay Time of Over-	TODISCHG	VDD = 3.6V ~ 2.4V	10	15	20	mS
	discharge
	Excess Current Threshold Voltage		Detect rising edge of “V-“ pin	0.15	0.17	0.19	V
	During Discharge		voltage
	Output Delay of Discharge Excess		VDD = 3.0V	15	20	25	mS
	Current
	Excess Current Threshold Voltage		Detect falling edge of “V-“ pin	-0.19	-0.17	-0.15	V
	During Charge		voltage
	Output Delay of Charge Excess			15	20	25	mS
	Current
	Short Detection Voltage During		VDD = 3.0V	VDD-1.1	VDD-0.8	VDD-0.5	V
	Discharge
	Output Delay of Discharge Short	TSHORT	VDD = 3.0V	--	5	50	µS
	Circuit
	Reset Resistance for Excess	RSHORT	VDD = 3.6V, V- = 1.0V	25	50	75	kΩ
	Current Protection
	Supply Current	IDD	VDD = 3.9V, V- = 0V	--	2.0	5.0	µA
	Standby Current	ISTANDBY	VDD = 2.0V	--	0.1	0.5	µA
	www.richtek-ic.com.tw				DS9541-05 August 2001

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Preliminary

RT9541

Table 1

	Part Number	Over	Over	Excess
		Charge	Discharge	Current
	RT9541ACE (R)	4.25V	2.3V	170mV
	RT9541BCE (R)	4.25V	2.4V	170mV
	RT9541CCE (R)	4.25V	2.5V	170mV
	RT9541DCE (R)	4.25V	2.6V	170mV
	RT9541ECE (R)	4.25V	2.7V	170mV
	RT9541FCE (R)	4.25V	2.8V	170mV
	RT9541GCE (R)	4.30V	2.3V	170mV
	RT9541HCE (R)	4.30V	2.4V	170mV
	RT9541ICE (R)	4.30V	2.5V	170mV
	RT9541JCE (R)	4.30V	2.6V	170mV

	Part Number	Over	Over	Excess
		Charge	Discharge	Current
	RT9541KCE (R)	4.30V	2.7V	170mV
	RT9541LCE (R)	4.30V	2.8V	170mV
	RT9541MCE (R)	4.35V	2.3V	170mV
	RT9541NCE (R)	4.35V	2.4V	170mV
	RT9541OCE (R)	4.35V	2.5V	170mV
	RT9541PCE (R)	4.35V	2.6V	170mV
	RT9541QCE (R)	4.35V	2.7V	170mV
	RT9541RCE (R)	4.35V	2.8V	170mV
	RT9541SCE (R)	4.35V	2.9V	170mV
	RT9541TCE (R)	4.25V	2.9V	170mV

Function Block Diagram

VDD

CT

_ +

VD1

_ +

VD2

VSS

Pin Description

	Level Shift
+
_
VD4	Short
Delay	Circuit
	Detector
+
_
VD3

DOUT COUT V-

		Pin Number		Pin Name	Pin Function
	RT9541- CE		RT9541- CER
	1		3	COUT	Output of Over-charge Detection, CMOS Output
	2		4	CT	Pin for External Capacitor Setting Output Delay of VD1
	3		6	VSS	Ground
	4		1	DOUT	Output of Over-discharge Detection, CMOS Output
	5		5	VDD	Power Supply, through a Resistor (R1)
	6		2	V-	Pin for Charger Negative Input, through a Resistor (R2)
DS9541-05		August 2001			www.richtek-ic.com.tw
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