NT1792
2
nd
Battery Protection IC for 4-Cell
Features
4-Cell Secondary Protection
High Accuracy Overcharge Voltage:
4.350V to 4.500V (50mV steps)
±25mV
Programmable Delay Time, or Optional Internal
Delay Time (1.8sec typically)
Low Power Consumption:
At 3.5V for each cell: 3.3µA max. (+25
℃
)
High Input-Voltage Device
Absolute Maximum Rating: 40V
Operating Voltage range: 5.5V to 26V
High Ripple Rejection Ability for Power Supply
Package: NMSOP-8L, UMSOP-8L, MISDFN-8L
Descriptions
NT1792 is an accurate secondary battery protection
IC for all 4-cell battery packs. A programmable
external delay circuit and an internal delay circuit are
both embedded for overcharge detection delay time.
The comparators with a precise reference are built on
each VCx pin detecting cell voltages. If one of the cell
voltage goes greater than the overcharge detection
voltage, NT1792 starts discharging the external delay
capacitor C
CD
until the voltage of CD pin is lower than
1.11V. After that, the Out pin inverses from a low
state to a high state to blow the fuse.
Applications
Notebook PCs
Portable Instrumentation
Medical and Test Equipment
Typical Application Circuit
SC PROTECTOR
NT1792
RVDD
EB+
VC4
VDD
CVDD
J1
BAT1
BAT2
BAT3
BAT4
1
R4
R3
R2
C4
VC3
C3
VC2
C2
VC1
OUT
CD
CCD
R1
C1
GND
RVSS
EB-
High Side Application for 4-Cell Protection
Neotec Semiconductor Ltd.
www.neotec.com.tw
1/18
NT1792DS V2.41 2012/9/17
NT1792
Ordering Information
NT1792-XX XX
Package Type
M1: NMSOP-8L
M2: UMSOP-8L
BD: MISDFN-8L
Version Type
Marking Information
N/UMSOP-8L
Top view
MISDFN-8L
Top view
(1)(2)(3)(4)
(5)(6)(7)(8)
1
2
3
4
(1)(2)(3)(4)
(5)(6)(7)(8)
8
7
6
5
(1)(2)
(3)(4)
: Product Code
: Version Type
(5)(6)(7)(8) : Lot Number
Product
Code
AR
AR
AR
Version
Type
A0
A1
A5
Overcharge Detection
Voltage (V
CU
) (V)
4.50
±
0.025
4.45
±
0.025
4.35
±
0.025
Overcharge Hysteresis
Overcharge detection
delay time (t
CU
) (s)
Voltage (V
CH
) (V)
0.38
±
0.1
0.38
±
0.1
0.045
±
0.02
2.5
±
35%
@ CCD=0.1
µ
F
Output Form
CMOS output active “H”
CMOS output active “H”
CMOS output active “H”
For any changes to the detection voltage or other parameters, please contact Neotec.
Neotec Semiconductor Ltd.
www.neotec.com.tw
2/18
NT1792DS V2.41 2012/9/17
NT1792
Pin Descriptions and Description
N/UMSOP-8L
Top view
8
7
6
5
MISDFN-8L
Top view
1
2
3
4
1
Pin No.
1
2
3
4
5
6
7
8
Name
OUT
VDD
CD
VC1
GND
VC2
VC3
VC4
8
7
6
5
2
3
4
Descriptions
Active output pin to control the external MOSFET.
Power supply Input.
An external capacitor is connected to determine the programmable delay time.
Cell Voltage Input (the least positive cell).
Ground Pin.
Cell Voltage Input (the third most positive cell).
Cell Voltage Input (the second most positive cell).
Cell Voltage Input (the most positive cell).
Absolute Maximum Ratings
Symbol
V
DD
–V
GND
V
CD
V
IN
V
OUT
Topr
Tstg
Descriptions
Voltage between VDD - GND pin
Delay capacitor connection pin voltage
Battery cell voltage input pin
Output pin voltage (OUT pin)
Operating free-air temperature
Storing temperature range
MIN
-0.3
V
GND
-0.3
V
GND
-0.3
V
GND
-0.3
-40
-40
MAX
40
7.5
V
DD
+0.3
V
DD
+0.3
85
125
Units
V
V
V
V
°C
°C
Neotec Semiconductor Ltd.
www.neotec.com.tw
3/18
NT1792DS V2.41 2012/9/17
NT1792
Electrical Characteristics
Symbol
V
DSOP
I
OPE1
I
OPE2
I
VC4
I
VC3
I
VC2
I
VC1
V
CU
Description
Operating Voltage
Consumption current 1
Conditions
--
MIN
5.5
--
--
-0.3
-0.3
-0.3
-0.3
V
CU
-0.025
0.280
0.025
1.625
--
--
V
DD
-0.05
--
(VC4-VC3)=(VC3-VC2)=(VC2-VC1)
=(VC1-GND)=3.5V
V
GND
--
TYP
--
2.5
2.45
--
--
--
--
V
CU
0.380
0.045
2.50
2
--
--
3.3
MAX
26
3.3
3.3
0.3
0.3
0.3
0.3
V
CU
+0.025
0.480
0.065
3.375
5
VDD
V
GND
+0.05
--
Ta=25
℃
Units
V
µA
µA
µA
µA
µA
µA
V
V
V
Sec
mS
V
V
V
(VC4-VC3)=(VC3-VC2)=(VC2-VC1)
=(VC1-GND)=3.5V
(VC4-VC3)=(VC3-VC2)=(VC2-VC1)
Consumption current 2
=(VC1-GND)=2.3V
(VC4-VC3)=(VC3-VC2)=(VC2-VC1)
VC4 sink current
=(VC1-GND)=3.5V
(VC4-VC3)=(VC3-VC2)=(VC2-VC1)
VC3 sink current
=(VC1-GND)=3.5V
(VC4-VC3)=(VC3-VC2)=(VC2-VC1)
VC2 sink current
=(VC1-GND)=3.5V
(VC4-VC3)=(VC3-VC2)=(VC2-VC1)
VC1 sink current
=(VC1-GND)=3.5V
Overcharge detection
V
OUT
=L H
voltage
Overcharge hysteresis
V
OUT
=H L
voltage
Overcharge detection
C
CD
=0.1µF
delay time
Overcharge timer reset
delay time
Output “H” voltage
Output “L” voltage
CD pin high voltage
I
OUT
=10µA
A0, A1 Version
A5
Version
V
CH
t
CU
t
TR
V
OUT(H)
V
OUT(L)
V
CD
Neotec Semiconductor Ltd.
www.neotec.com.tw
4/18
NT1792DS V2.41 2012/9/17
NT1792
Electrical Characteristics (continued)
Symbol
V
DSOP
I
OPE1
I
OPE2
I
VC4
I
VC3
I
VC2
I
VC1
V
CU
Description
Operating Voltage
Consumption current 1
Conditions
--
MIN
5.5
--
--
-0.3
-0.3
-0.3
-0.3
V
CU
-0.050
0.280
0.025
0.5
--
--
V
DD
-0.05
--
(VC4-VC3)=(VC3-VC2)=(VC2-VC1)
=(VC1-GND)=3.5V
V
GND
--
TYP
--
2.5
2.45
--
--
--
--
V
CU
0.380
0.045
2.5
2
--
--
3.3
Ta=-40
℃
~85
℃
MAX
26
4.5
4.5
0.3
0.3
0.3
0.3
V
CU
+0.050
0.480
0.065
4.5
8
VDD
V
GND
+0.05
--
Units
V
µA
µA
µA
µA
µA
µA
V
V
V
Sec
mS
V
V
V
V
CH
(VC4-VC3)=(VC3-VC2)=(VC2-VC1)
=(VC1-GND)=3.5V
(VC4-VC3)=(VC3-VC2)=(VC2-VC1)
Consumption current 2
=(VC1-GND)=2.3V
(VC4-VC3)=(VC3-VC2)=(VC2-VC1)
VC4 sink current
=(VC1-GND)=3.5V
(VC4-VC3)=(VC3-VC2)=(VC2-VC1)
VC3 sink current
=(VC1-GND)=3.5V
(VC4-VC3)=(VC3-VC2)=(VC2-VC1)
VC2 sink current
=(VC1-GND)=3.5V
(VC4-VC3)=(VC3-VC2)=(VC2-VC1)
VC1 sink current
=(VC1-GND)=3.5V
Overcharge detection
V
OUT
=L H
voltage
A0, A1
Version
Overcharge hysteresis
V
OUT
=H L
voltage
A5 Version
Overcharge detection
C
CD
=0.1µF
delay time
Overcharge timer reset
delay time
Output “H” voltage
Output “L” voltage
CD pin high voltage
I
OUT
=10µA
t
CU
t
TR
V
OUT(H)
V
OUT(L)
V
CD
Neotec Semiconductor Ltd.
www.neotec.com.tw
5/18
NT1792DS V2.41 2012/9/17