RICOH R5460x Technical data

R5460x SERIES

Li-ION/POLYMER 2-CELL PROTECTOR

NO.EA-165-091221

OUTLINE

The R5460xxxxxx Series are high voltage CMOS-based protection ICs for over-charge/discharge of rechargeable two-cell Lithium-ion (Li+) / Lithium polymer, further include a short circuit protection circuit for preventing large external short circuit current and the protection circuits against the excess discharge-current and excess charge current.

Each of these ICs is composed of six voltage detectors, a reference unit, a delay circuit, a short circuit protector, an oscillator, a counter, and a logic circuit. When the over-charge voltage threshold or excess-charge current threshold crosses the each detector threshold from a low value to a high value, the output of COUT pin switches to “L” level after internal fixed delay time. To release over-charge detector after detecting over-charge, the detector can be reset and the output of COUT becomes "H" when a kind of load is connected to VDD after a charger is disconnected from the battery pack and the cell voltage becomes lower than over-charge detector threshold. In case that a charger is continuously connected to the battery pack, if the cell voltage becomes lower than the over-charge detector threshold, over-charge state is also released.

The output of DOUT pin, the output of the over-discharge detector and the excess discharge-current detector, switches to “L” level after internally fixed delay time, when discharged voltage crosses the detector threshold from a high value to a value lower than VDET2.

The conditions to release over-discharge voltage detector after detecting over-discharge voltage are as follows:

A/D versions: after connecting a charger, when the cell voltage becomes higher than over-discharge detector threshold or, without connecting charger, when the cell voltage becomes equal or higher than over-discharge released voltage.

C version: after connecting a charger, when the cell voltage becomes higher than over-discharge detector threshold voltage.

E version: whether connecting a charger, or not, when the cell voltage becomes higher than released voltage from over-discharge.

F version: after connecting a charger, when the cell voltage becomes higher than released voltage from over-discharge.

In case that connecting a charger, for A/C/D versions, there is no hysteresis for over-discharge detector. For E/F versions, even if a charger is connected to the battery pack, the hysteresis of over-discharge detector exists.

To satisfy the release conditions for over-discharge voltage protector, the output voltage of DOUT becomes "H".

Even if a battery is discharged to 0V, charge current is acceptable.

After detecting excess-discharge current or short current, when the load is disconnected, the excess discharged or short condition is released and DOUT becomes “H”.

After detecting over-discharge voltage, supply current will be kept extremely low by halting internal circuits' operation.

When the output of COUT is “H”, if V- pin level is set at -1.6V, the delay time of detector can be shortened. Especially, the delay time of the over-charge detector can be reduced into approximately 1/60 and test time for protection circuit PCB can be reduced. The output type of COUT and DOUT is CMOS.

1

R5460x

FEATURES

Manufactured with High Voltage Tolerant Process ................		Absolute Maximum Rating		30V
Low supply current ........................................	Supply current (At normal mode)			Typ. 4.0μΑ
	Standby current		Typ. 1.2μΑ( A/ D/ E version )
			Max. 0.1μΑ( C/ F version )
High accuracy detector threshold ..........................................		Over-charge detector (Topt=25°C)		±25mV
			(Topt=-5 to 55°C)	±30mV
		Over-discharge detector		±2.5%
		Excess discharge-current detector		±15mV
		Excess charge-current detector		±40mV
Variety of detector threshold
Over-charge detector threshold( A/ C/ E/ F version )			4.1V-4.5V step of 0.005V(VD1U / VD1L)
Over-discharge detector threshold( D version )			3.5V-4.0V step of 0.005V(VD1U / VD1L)
Over-discharge detector threshold			2.0V-3.0V step of 0.005V(VD2U / VD2L)
Excess charge-current threshold			0.05V-0.20V step of 0.005V
	3 options of Excess charge-current threshold (1) -0.4V±40mV
	.......................................................................		(2) -0.2V±30mV
	.......................................................................		(3) -0.1V±30mV
Over-charge released voltage			0.1V-0.4V step of 0.05V(VH1U / VH1L)
Over-discharge released voltage			0.2V-0.7V step of 0.1V(VH2U / VH2L)
Short Detector Threshold			Fixed at 0.8V
Internal fixed Output delay time .............	Over-charge detector Output Delay 1.0s
	Over-discharge detector Output Delay			128ms
	Excess charge-current detector Output Delay			8ms
	Short Circuit detector Output Delay			300µs

Output Delay Time Shortening Function	...............At COUT is “H”, if V- level is set at –1.6V, the Output Delay
	time of detect and release the over-charge and
	over-discharge can be reduced.
	(Delay Time for over-charge becomes about 1/60 of normal state.)
0V-battery charge ...................................................................	acceptable
Ultra Small package ...............................................................	SOT-23-6,DFN(PLP)1820-6

APPLICATIONS

Li+ / Li Polymer protector of over-charge, over-discharge, excess-current for battery pack

High precision protectors for cell-phones and any other gadgets using on board Li+ / Li Polymer battery

2

R5460x

BLOCK DIAGRAMS

A/ D/ E/ F version

VDD
VD1U			DS Circuit
	scillator	Counter
		Logic	Level
		Circuit	Shift
		Delay	Short
VD2U			Detector
Vc
	VD4
VD1L		Logic
		Circuit
VD2L	VD3
VSS		DOUT	COUT	V-

C version

VDD
VD1U			DS Circuit
	scillator	Counter
		Logic	Level
			Shift
		Circuit
		Delay	Short
VD2U			Detector
Vc
	VD4
VD1L		Logic
		Circuit

VD2L

VD3

VSS

DOUT COUT

V-

3

R5460x

SELECTION GUIDE

In the R5460xxxxxx Series, input threshold of over-charge, over-discharge, excess discharge current, and the package and taping can be designated.

Part Number is designated as follows:

R5460x xxxxx-xx← Part Number

		↑	↑	↑↑	↑
		a	b	c d	e
	Code				Contents
	a	Package Type N: SOT-23-6 K:DFN(PLP)1820-6
	b	Serial Number for the R5402 Series designating input threshold for over-charge,
		over-discharge, excess discharge-current detectors.
	c	Designation of Output delay option of over-charge and excess discharge-current.
	d	Designation of version symbols
	e	Taping Type: TR (refer to Taping Specification)

PIN CONFIGURATIONS

	SOT-23-6				DFN(PLP)1820-6
6	5			4	6	5	4

					mark side
		mark side

1 2 3

1 2 3

4

R5460x

PIN DESCRIPTIONS

	Pin No.		Symbol	Description
	SOT23-6	PLP1820-6
	1	3	DOUT	Output pin of over-discharge detection, CMOS output
	2	1	COUT	Output pin of over-charge detection, CMOS output
	3	2	V-	Pin for charger negative input
	4	6	VC	Input Pin of the center voltage between two-cell
	5	5	VDD	Power supply pin, the substrate voltage level of the IC.
	6	4	VSS	Vss pin. Ground pin for the IC

The backside tab of DFN(PLP)1820-6 package is connected to the substrate level. (VDD) Note that avoiding short with other level.

ABSOLUTE MAXIMUM RATINGS

Symbol	Item	Ratings	Unit
VDD	Supply voltage	-0.3 to 12	V
	Input voltage
Vc	Center pin voltage between two-cell	VSS -0.3 to VDD+0.3	V
V-	Charger negative input V- pin	VDD -30 to VDD+0.3
	Output voltage
VCOUT	COUT pin	VDD -30 to VDD + 0.3	V
VDOUT	DOUT pin	VSS -0.3 to VDD + 0.3	V
PD	Power dissipation	150	mW
Topt	Operating temperature range	-40 to 85	°C
Tstg	Storage temperature range	-55 to 125	°C

*Note: Exposure to the condition exceeded Absolute Maximum Ratings may cause the permanent damages and affects the reliability and safety of both device and systems using the device.

The functional operations cannot be guaranteed beyond specified values in the Recommended conditions.

5

R5460x

ELECTRICAL CHARACTERISTICS

R5460x2xxAA/AD/AE version

Unless otherwise specified, Topt=25°C

Symbol

Item

Conditions

Min.

Typ.

Max.

Unit

Note1

VDD1

Operating input voltage

Voltage defined as VDD-Vss

1.5

10.0

V

A

Vst

Minimum operating Voltage

Voltage defined as VDD-V-

1.8

V

A

for 0V charging

*Note 1

VDD-Vss=0V

VDET1U

Detect rising edge of supply

VDET1U-0.025

VDET1U

VDET1U+0.025

V

B

CELL1 Over-charge threshold

Voltage R1=330Ω

VDET1U-0.030

VDET1U

VDET1U+0.030

V

B

R1=330Ω (Topt=-5 to 55°C)*Note3

REL1U

CELL1 Over-charge

R1=330Ω

REL1U

-0.050

REL1U

V

REL1U

V

B

V

released voltage

V

V

+0.050

tVDET1

Output delay of over-charge

VDD=3.2V to 4.5V, Vc-Vss=3.2V

0.7

1.0

1.3

s

B

tVREL1

Output delay of release from

VDD=4.5V to 3.2V, Vc-Vss=3.2V

11

16

21

ms

B

over-charge

VDET1L

CELL2 Over-charge detector

Detect rising edge of supply

VDET1L-0.025

VDET1L

VDET1L+0.025

V

C

voltage

R2=330Ω

threshold

*Note3

VDET1L-0.030

VDET1L

VDET1L+0.030

V

C

R2=330Ω

(Topt=-5 to 55°C)

VREL1L

CELL2 Over-charge released voltage

R2=330Ω

REL1L

-0.05

REL1L

REL1L

+0.05

V

C

V

V

V

VDET2U

CELL1 Over-discharge threshold

Detect falling edge of supply

×

VDET2U

×

V

D

voltage

VDET2U

0.975

VDET2U

1.025

VREL2U

CELL1 Released Voltage from

Detect rising edge of supply

×

0.975

VREL2U

×

1.025

V

D

Over-discharge

voltage

VREL2U

VREL2U

tVDET2

Output delay of over-discharge

VDD=3.2V to 1.9V, Vc-Vss=3.2V

89

128

167

ms

D

tVREL2

Output delay of release from

VDD=1.9V to 3.2V, Vc-Vss=3.2V

0.7

1.2

1.7

ms

D

over-discharge

VDET2L

CELL2 Over-discharge threshold

Detect falling edge of supply

VDET2L×0.975

VDET2L

VDET2L×1.025

V

E

voltage

VREL2L

CELL2 Released Voltage from

Detect rising edge of supply

VREL2L

×

VREL2L

VREL2L

×

V

E

Over-discharge

voltage

0.975

1.025

VDET3

Excess discharge-current

Detect rising edge of 'V-' pin

VDET3-0.015

VDET3

VDET3+0.015

V

F

Threshold

voltage

tVDET3

Output delay of excess discharge

VDD-Vc=Vc-Vss=3.2V,

8

12

16

ms

F

current

V-=0V to 0.5V

tVREL3

Output delay of release from

VDD-Vc=Vc-Vss=3.2V,

0.7

1.2

1.7

ms

F

excess discharge-current

V-=3V to 0V

DET4

Excess charge-current threshold

Detect falling edge of 'V-' pin

-0.44

-0.40

-0.36

V

G

-0.23

-0.20

-0.17

V

voltage

-0.13

-0.10

-0.07

tVDET4

Output delay of excess charge-current

VDD-Vc=Vc-Vss=3.2V,

5

8

11

ms

G

V-=0V to -1V

tVREL4

Output delay of release from

VDD-Vc=Vc-Vss=3.2V,

0.7

1.2

1.7

ms

G

excess charge-current

V-=-1V to 0V

Vshort

Short protection voltage

VDD-Vc=Vc-Vss=3.2V

0.7

1.1

1.5

V

F

tshort

Output Delay of Short protection

VDD-Vc=Vc-Vss=3.2V,

150

300

500

µs

F

V-=0V to 6.4V

Rshort

Reset resistance for Excess

VDD-Vc=Vc-Vss=3.2V, V-=1V

25

40

75

kΩ

F

discharge-current protection

VDS

Delay Shortening Mode input voltage

VDD-Vc=Vc-Vss=4.0V

-2.2

-1.6

-1.0

V

G

VOL1

Nch ON voltage of COUT

Iol=50µA VDD-Vc=Vc-Vss=4.5V

0.4

0.5

V

H

VOH1

Pch ON voltage of COUT

Ioh=-50µA VDD-Vc=Vc-Vss=3.2V

6.8

7.4

V

I

VOL2

Nch ON voltage of DOUT

Iol=50µA VDD-Vc=Vc-Vss=1.9V

0.2

0.5

V

J

VOH2

Pch ON voltage of DOUT

Ioh=-50µA, VDD-Vc=Vc-Vss=3.2V

6.8

7.4

V

K

IDD

Supply current

VDD-Vc=Vc-Vss=3.2V, V-=0V

4.0

8.0

µA

L

IS

Standby current

VDD-Vc=Vc-Vss=1.9V

1.2

2.0

µA

L

*Note: We compensate for this characteristic related to temperature by laser-trim, however, this specification is guaranteed by design, not production tested.

*Note2: Indicates test circuits shown in 19-20 page.

6

R5460x

R5460x2xxAC version

Unless otherwise specified, Topt=25°C

Symbol

Item

Conditions

Min.

Typ.

Max.

Unit

Note1

VDD1

Operating input voltage

Voltage defined as VDD-Vss

1.5

10.0

V

A

Vst

Minimum operating Voltage

Voltage defined as VDD-V-

1.8

V

A

for 0V charging

*Note 1

VDD-Vss=0V

VDET1U

Detect rising edge of supply

VDET1U-0.025

VDET1U

VDET1U+0.025

V

B

CELL1 Over-charge threshold

Voltage R1=330Ω

VDET1U-0.030

VDET1U

VDET1U+0.030

V

B

R1=330Ω (Topt=-5 to 55°C)*Note3

REL1U

CELL1 Over-charge

R1=330Ω

REL1U

-0.050

REL1U

REL1U

V

B

V

released voltage

V

V

V

+0.050

tVDET1

Output delay of over-charge

VDD=3.2V to 4.5V, Vc-Vss=3.2V

0.7

1.0

1.3

s

B

tVREL1

Output delay of release from

VDD=4.5V to 3.2V, Vc-Vss=3.2V

11

16

21

ms

B

over-charge

VDET1L

CELL2 Over-charge detector

Detect rising edge of supply

VDET1L-0.025

VDET1L

VDET1L+0.025

V

C

voltage

R2=330Ω

threshold

*Note3

VDET1L-0.030

VDET1L

VDET1L+0.030

V

C

R2=330Ω

(Topt=-5 to 55°C)

VREL1L

CELL2 Over-charge released voltage

R2=330Ω

REL1L

-0.05

REL1L

V

REL1L

+0.05

V

C

V

V

VDET2U

CELL1 Over-discharge threshold

Detect falling edge of supply

×

VDET2U

×

V

D

voltage

VDET2U

0.975

VDET2U

1.025

tVDET2

Output delay of over-discharge

VDD=3.2V to 1.9V, Vc-Vss=3.2V

89

128

167

ms

D

tVREL2

Output delay of release from

VDD=1.9V to 3.2V, Vc-Vss=3.2V

0.7

1.2

1.7

ms

D

over-discharge

VDET2L

CELL2 Over-discharge threshold

Detect falling edge of supply

VDET2L×0.975

VDET2L

VDET2L×1.025

V

E

voltage

VDET3

Excess discharge-current

Detect rising edge of 'V-' pin

VDET3-0.015

VDET3

VDET3+0.015

V

F

Threshold

voltage

tVDET3

Output delay of excess discharge

VDD-Vc=Vc-Vss=3.2V,

8

12

16

ms

F

current

V-=0V to 0.5V

tVREL3

Output delay of release from

VDD-Vc=Vc-Vss=3.2V,

0.7

1.2

1.7

ms

F

excess discharge-current

V-=3V to 0V

DET4

Excess charge-current threshold

Detect falling edge of 'V-' pin

-0.44

-0.40

-0.36

V

G

-0.23

-0.20

-0.17

V

voltage

-0.13

-0.10

-0.07

tVDET4

Output delay of excess charge-current

VDD-Vc=Vc-Vss=3.2V,

5

8

11

ms

G

V-=0V to -1V

tVREL4

Output delay of release from

VDD-Vc=Vc-Vss=3.2V,

0.7

1.2

1.7

ms

G

excess charge-current

V-=-1V to 0V

Vshort

Short protection voltage

VDD-Vc=Vc-Vss=3.2V

0.7

1.1

1.5

V

F

tshort

Output Delay of Short protection

VDD-Vc=Vc-Vss=3.2V,

150

300

500

µs

F

V-=0V to 6.4V

Rshort

Reset resistance for Excess

VDD-Vc=Vc-Vss=3.2V, V-=1V

25

40

75

kΩ

F

discharge-current protection

VDS

Delay Shortening Mode input voltage

VDD-Vc=Vc-Vss=4.0V

-2.2

-1.6

-1.0

V

G

VOL1

Nch ON voltage of COUT

Iol=50µA VDD-Vc=Vc-Vss=4.5V

0.4

0.5

V

H

VOH1

Pch ON voltage of COUT

Ioh=-50µA VDD-Vc=Vc-Vss=3.2V

6.8

7.4

V

I

VOL2

Nch ON voltage of DOUT

Iol=50µA VDD-Vc=Vc-Vss=1.9V

0.2

0.5

V

J

VOH2

Pch ON voltage of DOUT

Ioh=-50µA, VDD-Vc=Vc-Vss=3.2V

6.8

7.4

V

K

IDD

Supply current

VDD-Vc=Vc-Vss=3.2V, V-=0V

4.0

8.0

µA

L

IS

Standby current

VDD-Vc=Vc-Vss=1.9V

0.1

µA

L

*Note: We compensate for this characteristic related to temperature by laser-trim, however, this specification is guaranteed by design, not production tested.

*Note2: Indicates test circuits shown in 19-20 page.

7

R5460x

R5460x2xxAF version

	Symbol	Item		Conditions
	VDD1	Operating input voltage	Voltage defined as VDD-Vss
	Vst	Minimum operating Voltage	Voltage defined as VDD-V-
		for 0V charging *Note 1	VDD-Vss=0V
	VDET1U		Detect rising edge of supply
		CELL1 Over-charge threshold	Voltage	R1=330Ω
			R1=330Ω (Topt=-5 to 55°C)*Note3
	REL1U	CELL1 Over-charge	R1=330Ω
	V	released voltage
	tVDET1	Output delay of over-charge	VDD=3.2V to 4.5V, Vc-Vss=3.2V
	tVREL1	Output delay of release from	VDD=4.5V to 3.2V, Vc-Vss=3.2V
		over-charge
	VDET1L	CELL2 Over-charge detector	Detect rising edge of supply
			voltage	R2=330Ω
		threshold
			R2=330Ω (Topt=-5 to 55°C)*Note3
	VREL1L	CELL2 Over-charge released voltage	R2=330Ω
	VDET2U	CELL1 Over-discharge threshold	Detect falling edge of supply
			voltage
	VREL2U	CELL1 Released Voltage from	Detect rising edge of supply
		Over-discharge	voltage
	tVDET2	Output delay of over-discharge	VDD=3.2V to 1.9V, Vc-Vss=3.2V
	tVREL2	Output delay of release from	VDD=1.9V to 3.2V, Vc-Vss=3.2V
		over-discharge
	VDET2L	CELL2 Over-discharge threshold	Detect falling edge of supply
			voltage
	VREL2L	CELL2 Released Voltage from	Detect rising edge of supply
		Over-discharge	voltage
	VDET3	Excess discharge-current	Detect rising edge of 'V-' pin
		Threshold	voltage
	tVDET3	Output delay of excess discharge	VDD-Vc=Vc-Vss=3.2V,
		current	V-=0V to 0.5V
	tVREL3	Output delay of release from	VDD-Vc=Vc-Vss=3.2V,
		excess discharge-current	V-=3V to 0V
	VDET4	Excess charge-current threshold	Detect falling edge of 'V-' pin
			voltage
	tVDET4	Output delay of excess charge-current	VDD-Vc=Vc-Vss=3.2V,
			V-=0V to -1V
	tVREL4	Output delay of release from	VDD-Vc=Vc-Vss=3.2V,
		excess charge-current	V-=-1V to 0V
	Vshort	Short protection voltage	VDD-Vc=Vc-Vss=3.2V
	tshort	Output Delay of Short protection	VDD-Vc=Vc-Vss=3.2V,
			V-=0V to 6.4V
	Rshort	Reset resistance for Excess	VDD-Vc=Vc-Vss=3.2V, V-=1V
		discharge-current protection
	VDS	Delay Shortening Mode input voltage	VDD-Vc=Vc-Vss=4.0V
	VOL1	Nch ON voltage of COUT	Iol=50µA VDD-Vc=Vc-Vss=4.5V
	VOH1	Pch ON voltage of COUT	Ioh=-50µA VDD-Vc=Vc-Vss=3.2V
	VOL2	Nch ON voltage of DOUT	Iol=50µA VDD-Vc=Vc-Vss=1.9V
	VOH2	Pch ON voltage of DOUT	Ioh=-50µA, VDD-Vc=Vc-Vss=3.2V
	IDD	Supply current	VDD-Vc=Vc-Vss=3.2V, V-=0V
	IS	Standby current	VDD-Vc=Vc-Vss=1.9V

Unless otherwise specified, Topt=25°C

Min.		Typ.	Max.		Unit	Note1
1.5			10.0		V	A
			1.8		V	A
VDET1U-0.025		VDET1U	VDET1U+0.025		V	B
VDET1U-0.030		VDET1U	VDET1U+0.030		V	B
VREL1U-0.050		VREL1U	VREL1U+0.050		V	B
0.7		1.0	1.3		s	B
11		16	21		ms	B
VDET1L-0.025		VDET1L	VDET1L+0.025		V	C
VDET1L-0.030		VDET1L	VDET1L+0.030		V	C
VREL1L-0.05
		VREL1L	VREL1L+0.05		V	C
×		VDET2U	×		V	D
VDET2U	0.975		VDET2U	1.025
×	0.975	VREL2U	×	1.025	V	D
VREL2U			VREL2U
89		128	167		ms	D
0.7		1.2	1.7		ms	D
VDET2L×0.975		VDET2L	VDET2L×1.025		V	E
×		VREL2L	×		V	E
VREL2L 0.975			VREL2L 1.025
VDET3-0.015		VDET3	VDET3+0.015		V	F
8		12	16		ms	F
0.7		1.2	1.7		ms	F
-0.44
		-0.40	-0.36		V	G
-0.23		-0.20	-0.17
-0.13		-0.10	-0.07
5		8	11		ms	G
0.7		1.2	1.7		ms	G
0.7		1.1	1.5		V	F
150		300	500		µs	F
25		40	75		kΩ	F
-2.2		-1.6	-1.0		V	G
		0.4	0.5		V	H
6.8		7.4			V	I
		0.2	0.5		V	J
6.8		7.4			V	K
		4.0	8.0		µA	L
			0.1		µA	L

*Note: We compensate for this characteristic related to temperature by laser-trim, however, this specification is guaranteed by design, not production tested.

*Note2: Indicates test circuits shown in 19-20 page.

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R5460x

OPERATION

VDET1U,VDET1L / Over-Charge Detectors

The VDET1U and VDET1L monitor the voltage between VDD pin and VC pin (the voltage of Cell1) and the voltage between VC pin and VSS pin (the voltage of Cell2), if either voltage becomes equal or more than the over-charge detector threshold, the over-charge is detected, and an external charge control Nch MOSFET turns off with COUT pin being at "L" level.

VDET1U is the detector of Cell1, and the VDET1L is the detector of Cell2.

To reset the over-charge and make the COUT pin level to "H" again after detecting over-charge, in such conditions that a time when the both Cell1 and Cell2 are down to a level lower than over-charge voltage, by connecting a kind of load to VDD after disconnecting a charger from the battery pack. Then, the output voltage of COUT pin becomes "H", and it makes an external Nch MOSFET turn on, and charge cycle is available. In other words, once over-charge is detected, even if the supply voltage becomes low enough, if a charger is continuously connected to the battery pack, recharge is not possible. Therefore this over-charge detector has no hysteresis. To judge whether or not load is connected, the built-in excess-discharge current detector is used. By connecting some load, V- pin voltage becomes equal or more than excess-discharge current detector threshold, and reset the over-charge detecting state.

Further, either or both voltage of Cell1 and Cell2 is higher than the over-charge detector threshold, if a charger is removed and some load is connected, COUT outputs “L”, however, load current can flow through the parasitic diode of the external charge control Nch MOSFET. After that, when the VDD pin voltage becomes lower than the over-charge detector threshold, COUT becomes “H”.

Internal fixed output delay times for over-charge detection and release from over-charge exist. If either or both of the voltage of Cell1 or Cell2 keeps its level more than the over-charge detector threshold, and output delay time passes, over-charge voltage is detected. Even when the voltage of Cell1 or Cell2 pin level becomes equal or higher level than VDET1 if these voltages would be back to a level lower than the over-charge detector threshold within a time period of the output delay time, the over-charge is not detected. Besides, after detecting over-charge, while the both of Cell1 and Cell2 voltages are lower than the over-charge detector threshold, even if a charger is removed and a load is connected, if the voltage is recovered within output delay time of release from over-charge, over-charge state is not released.

A level shifter incorporated in a buffer driver for the COUT pin makes the "L" level of COUT pin to the V - pin voltage and the "H" level of COUT pin is set to VDD voltage with CMOS buffer.

VDET2U,VDET2L / Over-Discharge Detectors

The VDET2U and VDET2L monitor the voltage between VDD pin and VC pin (Cell1 voltage) and the voltage between VC pin and VSS pin (Cell2 Voltage). When either of the cell1 or cell2 voltage becomes equal or less than the over-discharge detector threshold, the over-discharge is detected and discharge stops by the external discharge control Nch MOSFET turning off with the DOUT pin being at "L" level.

The conditions to release over-discharge voltage detector after detecting over-discharge voltage are as follows:

A/D versions: after connecting a charger, when the cell voltage becomes higher than over-discharge detector threshold or, without connecting charger, when the cell voltage becomes equal or higher than over-discharge released voltage.

C version: after connecting a charger, when the cell voltage becomes higher than over-discharge detector threshold voltage.

E version: whether connecting a charger, or not, when the cell voltage becomes higher than released voltage from over-discharge.

F version: after connecting a charger, when the cell voltage becomes higher than released voltage from over-discharge.

In case that connecting a charger, for A/C/D versions, there is no hysteresis for over-discharge detector. For E/F versions, even if a charger is connected to the battery pack, the hysteresis of over-discharge

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R5460x

detector exists.

When a cell voltage equals to zero, if the voltage of a charger is equal or more than 0V-charge minimum voltage (Vst), COUT pin becomes "H" and a system is allowable to charge.

The output delay time for over-discharge detect is fixed internally. Even if the voltage of Cell1 or Cell2 is down to equal or lower than the over-discharge detector threshold, if the voltage of Cell1 or Cell2 would be back to a level higher than the over-discharge detector threshold within a time period of the output delay time, the over-discharge is not detected. Output delay time for release from over-discharge is also set.

After detecting over-discharge, supply current would be reduced and be into standby by halting unnecessary circuits and consumption current of the IC itself is made as small as possible.

C version: after detecting over-discharge, all the circuits are halted and the R5460 will be into standby mode. Others: after detecting over-discharge, whole circuits except over-discharge released detector function are

halted, and the R5460 will be into standby mode.

The output type of DOUT pin is CMOS having "H" level of VDD and "L" level of VSS.

VDET3 /Excess discharge-current Detector, Short Circuit Protector

Both of the excess current detector and short circuit protection can work when the both of control FETs are in "ON" state.

When the V- pin voltage is up to a value between the short protection voltage Vshort /VDD and excess discharge-current threshold VDET3, VDET3 operates and further soaring of V- pin voltage higher than Vshort makes the short circuit protector enabled. This leads the external discharge control Nch MOSFET turns off with the DOUT pin being at "L" level.

An output delay time for the excess discharge-current detector is internally fixed.

A quick recovery of V- pin level from a value between Vshort and VDET3 within the delay time keeps the discharge control FET staying "H" state. Output delay time for Release from excess discharge-current detection is also set.

When the short circuit protector is enabled, the DOUT would be "L" and the delay time is also set.

The V - pin has a built-in pull-down resistor to the Vss pin, that is, the resistance to release from excess-discharge current.

After an excess discharge-current or short circuit protection is detected, removing a cause of excess discharge-current or external short circuit makes an external discharge control FET to an "ON" state automatically with the V- pin level being down to the VSS level through the built-in pulled down resistor. The reset resistor of excess discharge-current is off at normal state. Only when detecting excess discharge-current or short circuit, the resistor is on.

Output delay time of excess discharge-current is set shorter than the delay time for over-discharge detector. Therefore, if VDD voltage would be lower than VDET2 at the same time as the excess discharge-current is detected, the R5460xxxxxx is at excess discharge-current detection mode. By disconnecting a load, VDET3 is automatically released from excess discharge-current.

VDET4/ Excess charge-current detector

When the battery pack is chargeable and discharge is also possible, VDET4 senses V- pin voltage. For example, in case that a battery pack is charged by an inappropriate charger, an excess current flows, then the voltage of V- pin becomes equal or less than excess charge-current detector threshold. Then, the output of COUT becomes "L", and prevents from flowing excess current in the circuit by turning off the external Nch MOSFET.

Output delay of excess charge current is internally fixed. Even the voltage level of V- pin becomes equal or lower than the excess charge-current detector threshold, the voltage is higher than the VDET4 threshold within the delay time, the excess charge current is not detected. Output delay for the release from excess charge current is also set.

VDET4 can be released with disconnecting a charger and connecting a load.

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