LTC4110
Battery Backup
System Manager
FEATURES
n
DESCRIPTION
The LTC
®
4110 is a complete single chip, high efficiency,
flyback battery charge and discharge manager with auto-
matic switchover between the input supply and the backup
battery or super capacitor. The IC provides four modes of
operation: battery backup, battery charge, battery calibra-
tion and shutdown. Battery backup and battery charge are
automatic standalone modes, while the optional calibration
mode requires a CPU host to communicate over an SMBus.
During calibration the flyback charger is used in reverse
to discharge the battery with a programmable constant
current into the system load eliminating heat generation.
Three status outputs can be individually reconfigured over
the SMBus to become GPIOs. User programmable over-
discharge protection is provided. The SHDN pin isolates
the battery to support shipping the product with a charged
battery installed.
Multiple LTC4110s can be combined to form a redundant
battery backup system or increase the number of battery
packs to achieve longer backup run times.
The LTC4110 is available in a low profile (0.75mm), 38-pin
5mm
×
7mm QFN package. The QFN features an exposed
metal die mount pad for optimum thermal performance.
L,
LT, LTC and LTM are registered trademarks of Linear Technology Corporation. PowerPath
is a trademark of Linear Technology Corporation. All other trademarks are the property of their
respective owners.
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Complete Backup Battery Manager for Li-Ion/
Polymer, Lead Acid, NiMH/NiCd Batteries and
Super Capacitors
Charge and Discharge Battery with Voltages Above
and Below the Input Supply Voltage
“No Heat” Battery Calibration Discharge Using
System Load
Automatic Battery Backup with Input Supply
Removal Using PowerPath™ Control
Standalone for Li-Ion/Polymer, SLA, and Supercaps
Optional SMBus/I
2
C Support Allows Battery
Capacity Calibration Operation with Host
Over- and Under-Battery Voltage Protection
Adjustable Battery Float Voltage
Precision Charge Voltage ±0.5%
Programmable Charge/Calibration Current Up to
3A with ±3% Accuracy
Optional Temperature Qualified Charging
Wide Backup Battery Supply Range: 2.7V to 19V
Wide Input Supply Range: 4.5V to 19V
38-Lead (5mm
×
7mm) QFN Package
APPLICATIONS
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Backup Battery Systems
Server Memory Backup
Medical Equipment
High Reliability Systems
TYPICAL APPLICATION
Battery Backup System Manager
SYSTEM LOAD
DCIN
0V
OFF
ON
ON
BACKUP LOAD (DCOUT)
CURRENT FLOW
LTC4110
BATTERY
BACKUP
SYSTEM
MANAGER
BATTERY
HOST CPU
INID
UVLO
SET POINT
DCDIV
BATID
LTC4110
CHGFET
DCHFET
I
2
C BUS
4110 TA01b
Server Backup System (In Backup Mode)
SYSTEM LOAD
(DC/DC, ETC.)
BACKUP LOAD
(MEMORY, ETC.)
CURRENT FLOW
BATTERY
4110 F01
4110fa
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LTC4110
ABSOLUTE MAXIMUM RATINGS
(Note 1)
PIN CONFIGURATION
TOP VIEW
CHGFET
DCHFET
31 BAT
30 SELC
29 I
SENSE
28 SGND
27 CSN
39
26 CSP
25 I
TH
24 I
CHG
23 I
CAL
22 I
PCC
21 THB
20 THA
13 14 15 16 17 18 19
V
CAL
V
CHG
TIMER
V
DIS
V
REF
ACPb
TYPE
DCOUT
BATID
INID
V
DD
NC
DCIN, BAT, DCOUT, DCDIV, SHDN
to GND ....................................................... –0.3V to 20V
Input Voltage (CLP CLN) ...............–0.3V to DCIN + 0.3V
,
Input Voltage (CSP CSN) ................–0.3V to BAT + 0.3V
,
Input Voltage
(GPIO1, GPIO2, GPIO3, SELC, SELA, TYPE, V
CHG
,
THA, THB, I
SENSE
, ACPDLY, SDA, SCL) .... –0.3V to 7V
Input Voltage (V
CAL
, V
DIS
) ....................... –0.3V to 1.35V
Output Voltage
(ACPb, GPIO1, GPIO2, GPIO3) ................ –0.3V to 7V
CLP-CLN, CSP-CSN ..................................................±1V
Operating Temperature Range (Note 2)....–40°C to 85°C
Junction Temperature (Note 3) ............................. 105°C
Storage Temperature Range
QFN Package......................................–65°C to 125°C
38 37 36 35 34 33 32
DCIN 1
CLN 2
CLP 3
ACPDLY 4
DCDIV 5
SHDN 6
SDA 7
SCL 8
GPI01 9
GPI02 10
GPI03 11
SELA 12
UHF PACKAGE
38-LEAD (5mm 7mm) PLASTIC QFN
T
JMAX
= 100°C,
θ
JA
= 34°C/W
EXPOSED PAD (PIN 39) IS GND, MUST BE SOLDERED TO PCB
ORDER INFORMATION
LEAD FREE FINISH
LTC4110EUHF#PBF
LEAD BASED FINISH
LTC4110EUHF
TAPE AND REEL
LTC4110EUHF#TRPBF
TAPE AND REEL
LTC4110EUHF#TR
PART MARKING
4110
PART MARKING
4110
PACKAGE DESCRIPTION
38-Lead (5mm
×
7mm) Plastic QFN
PACKAGE DESCRIPTION
38-Lead (5mm
×
7mm) Plastic QFN
TEMPERATURE RANGE
–40°C to 85°C
TEMPERATURE RANGE
–40°C to 85°C
Consult LTC Marketing for parts specified with wider operating temperature ranges.
For more information on lead free part marking, go to:
http://www.linear.com/leadfree/
For more information on tape and reel specifications, go to:
http://www.linear.com/tapeandreel/
4110fa
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LTC4110
ELECTRICAL CHARACTERISTICS
SYMBOL
Power Input
DCIN
DCOUT
V
BAT
I
SPLY
I
BIDL
I
BBU
I
BSD
V
UVI
V
UVD
V
UVH
V
DD
V
DD(MIN)
V
FTOL
Operating Voltage Range
Operating Voltage Range
Operating Voltage Range
Supply Current (I
DCIN
+ I
DCOUT
) in Idle Mode
(Note 4)
Battery Current in Idle Mode (Notes 4 and 5)
Battery Current in Backup Mode (Note 5)
Battery Current in Shutdown (Note 5)
Undervoltage Lockout Exit Threshold
Undervoltage Lockout Entry Threshold
Undervoltage Lockout Hysteresis
Output Voltage
Output Voltage
Charge Float Voltage Accuracy
No Load
I
DD
= –10mA
l
l
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. Unless otherwise specified, V
DCIN
= V
DCOUT
= V
DCDIV
= 12V, V
BAT
= 8.4V,
GND = SGND = CLP = CLN = SHDN = 0V and R
VREF
= 49.9k. All currents into device pins are positive and all currents out of device pins
are negative. All voltages are referenced to GND, unless otherwise specified.
PARAMETER
CONDITIONS
Charge or Calibration Modes
Charge or Calibration Modes
Backup Mode
Backup Mode
l
l
l
l
MIN
4.5
4.5
2.7
2.7
TYP
MAX
19
19
19
19
UNITS
V
V
V
V
mA
μA
mA
μA
V
V
mV
2
30
V
DCIN
= 0
V
SHDN
= V
BAT
, V
DCIN
= 0
V
DCIN
Increasing
V
DCIN
Decreasing
l
l
3
45
3
45
4.45
4.1
2
20
3.7
3.4
4
3.7
400
4.5
4.25
–0.5
–0.8
–1
–2
4.75
V
DD
Regulator
5
V
V
0.5
0.8
1
2
%
%
%
%
Charging Performance
4.20V for Li-Ion. 2.35V for Lead Acid (Note 8)
V
CHG
= GND
–5°C < T
A
< 85°C (Note10)
l
–40°C < T
A
< 85°C
0.3V and –0.3V for Li-Ion Batteries,
0.15V and –0.15V for Lead Acid Batteries
(Note 8)
V
CSP
– V
CSN
=100mV
V
BAT
≥ 3.1V
–40°C < T
A
< 85°C
V
BAT
≥ 3.3V (Note 8), V
CSP
– V
CSN
= 10mV;
Li-Ion and NiMH/NiCd Batteries Only
V
BAT
≤ 3.3 (Note 8), V
CSP
– V
CSN
= 10mV;
Li-Ion and NiMH/NiCd Batteries Only
I
SKVA
I
SRCA
I
SKCA
I
VCHG
V
BC
V
BCH
V
AR
V
ARH
Voltage Error Amplifier Sink Current at I
TH
Pin V
ITH
= 2V
Current Error Amplifier Source Current at I
TH
V
ITH
= 2V
Pin
Current Error Amplifier Sink Current at I
TH
Pin V
ITH
= 2V
V
CHG
Pin Bias Current
Bulk Charge Threshold Voltage;
V
BAT
Increasing (Note 8)
Bulk Charge Threshold Voltage Hysteresis;
V
BAT
Decreasing (Note 8)
Auto Recharge Threshold Voltage;
V
BAT
Decreasing
Auto Recharge Threshold Hysteresis Voltage;
V
BAT
Increasing
V
CHG
= 1.25V
Li-Ion, V
CHG
= GND
NiMH/NiCd
Li-Ion, V
CHG
= GND
NiMH/NiCd
Standard Li-Ion Only;
Specified as Percentage of Float Voltage
Standard Li-Ion Only; Specified as
Percentage of Float Voltage
93
–100
2.80
0.84
3.00
0.90
85
40
95
2
97
l
V
FATOL
Charge Float Voltage Adjust Accuracy
I
BTOL
Bulk Charge Current Accuracy (Note 7)
–3
l
3
5
30
40
96
–24
24
100
3.20
0.96
%
%
%
%
μA
μA
μA
nA
V
V
mV
mV
%
%
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–5
–30
–40
I
PTOL
Preconditioning and Wake-Up Current
Accuracy (Note 7)
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LTC4110
ELECTRICAL CHARACTERISTICS
SYMBOL
V
BOV
PARAMETER
Battery Overvoltage Threshold;
V
BAT
Increasing
Battery Overvoltage Threshold Hysteresis;
V
BAT
Increasing.
Reference Pin Voltage Range
Programmed Timer Accuracy
Time Between Receiving Valid
ChargingCurrent() and ChargingVoltage()
Commands. Wake-Up Timer.
Calibration Cut-Off Default Voltage Accuracy;
V
BAT
Decreasing
2.75V for Li-Ion, 1.93V for Lead Acid,
V
CAL
= GND (Note 8), 0.95V for NiMH/NiCd
C
TIMER
= 47nF
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. Unless otherwise specified, V
DCIN
= V
DCOUT
= V
DCDIV
= 12V, V
BAT
= 8.4V,
GND = SGND = CLP = CLN = SHDN = 0V and R
VREF
= 49.9k. All currents into device pins are positive and all currents out of device pins
are negative. All voltages are referenced to GND, unless otherwise specified.
CONDITIONS
All Li-Ion, Lead Acid as Percentage of
Float Voltage
NiMH/NiCd (Note 8)
All Li-Ion, Lead Acid as Percentage of
Float Voltage
NiMH/NiCd (Note 8)
l
l
l
MIN
105
1.80
TYP
107.5
1.85
2
40
MAX
110
1.90
UNITS
%
V
%
mV
V
BOVH
V
REF
F
TMR
t
TIMEOUT
1.208
–15
140
1.220
0
175
1.232
15
210
V
%
sec
Calibration Performance
V
CTOL
V
CTOLH
l
–1.1
–1.3
85
50
40
1.1
1.3
%
%
mV
mV
mV
Calibration Cut-Off Default Voltage Hysteresis; Li-Ion
V
BAT
Increasing. (Note 8)
Lead Acid
NiMH/NiCd
Calibration Cut-Off Voltage Adjust Accuracy
Calibration Current Accuracy (Note 7)
V
CAL
Pin Leakage Current
Back-Drive Current Limit Threshold
±400mV for Li-Ion, ±300mV for Lead Acid,
±200mV for NiMH/NiCd (Note 8)
V
CSP
– V
CSN
= –100mV
V
CAL
= 1.25V
V
CLP
– V
CLN
Decreasing
V
CLN
= V
DCIN
l
l
l
V
CATOL
I
FTOL
I
VCAL
I
BDT
I
BDH
V
OVP
V
OVPH
–1.5
–5
–100
7
10
1
1.5
5
100
13
%
%
nA
mV
mV
Back-Drive Current Limit Threshold Hysteresis V
CLP
– V
CLN
Increasing
V
CLN
= V
DCIN
Calibration Mode Input Overvoltage
Comparator DCDIV Pin Threshold
Calibration Mode Input Overvoltage
Comparator DCDIV Pin Hysteresis
AC Present Comparator DCDIV Pin Threshold
AC Present Comparator DCDIV Pin Hysteresis
AC Present Comparator DCDIV Pin Input Bias
Current
V
DCDIV
Rising
V
DCDIV
Falling
l
1.4
1.5
100
1.6
V
mV
AC Present and Discharge Cut-Off Comparators
V
AC
V
ACH
I
AC
t
AC
V
DTOL
V
DTOLH
V
DCDIV
Falling
V
DCDIV
Rising
V
DCDIV
= 1.25V
l
1.196
1.22
50
1.244
100
V
mV
nA
ACPb Pin Externally Programmed Falling Delay C
ACPDLY
= 100nF R
VREF
= 49.9k,
,
V
DCDIV
Stepped From 1.17V to 1.30V
Discharge Cut-Off Default Voltage Accuracy;
V
BAT
Decreasing
Discharge Cut-Off Default Voltage Hysteresis;
V
BAT
Increasing (Note 8)
Discharge Cut-Off Voltage Adjust Accuracy
V
DIS
Pin Bias Current
2.75V for Li-Ion, 1.93V for Lead Acid,
V
DIS
= GND, 0.95V for NiMH/NiCd
Li-Ion
Lead acid
NiMH/NiCd
±400mV for Li-Ion, ±300mV for Lead Acid,
±200mV for NiMH/NiCd
V
DIS
= 1.25V
l
l
8
–1.5
10
12
1.5
ms
%
mV
mV
mV
85
50
40
2
–100
2
100
V
DATOL
I
VDIS
%
nA
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LTC4110
ELECTRICAL CHARACTERISTICS
SYMBOL
V
FR
V
REV
V
GON
V
GOFF
V
FO
PARAMETER
Forward Regulation Voltage (V
DCIN
-V
DCOUT
,
V
BAT
-V
DCOUT
)
Reverse Voltage Turn-Off Voltage
(V
DCIN
-V
DCOUT
, V
BAT
-V
DCOUT
)
“ON” Gate Clamping Voltage (V
DCIN
-V
INID
,
V
BAT
-V
BATID
)
The
l
denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. Unless otherwise specified, V
DCIN
= V
DCOUT
= V
DCDIV
= 12V, V
BAT
= 8.4V,
GND = SGND = CLP = CLN = SHDN = 0V and R
VREF
= 49.9k. All currents into device pins are positive and all currents out of device pins
are negative. All voltages are referenced to GND, unless otherwise specified.
CONDITIONS
2.7V ≤ V
DCIN
≤ 19V
2.7V ≤ V
DCIN
≤ 19V
I
INID
, I
BATID
= 1μA
l
l
MIN
10
–30
7
TYP
20
–18
8.3
MAX
32
–8
9.7
0.25
UNITS
mV
mV
V
V
mV
Input and Battery Ideal Diodes and Switches
“OFF” Gate Voltage (V
DCIN
-V
INID
, V
BAT
-V
BATID
) I
INID
, I
BATID
= –10μA
V
SHDN
= 0V and V
DCIN
(Shutdown)
BATID Fast-On Voltage Comparator Threshold
INID Pin Delay Times
I
BATID
> 500μA
C
INID
= 10nF
DCIN is Switched Between 12.2V and 11.8V
From DCOUT – V
GOFF
to DCOUT –6V
From DCOUT – V
GON
to DCOUT –1.5V
C
BATID
= 2.5nF
BAT is Switched Between 12.2V and 11.8V
From DCOUT – V
GOFF
to DCOUT –6V
From DCOUT – V
GON
to DCOUT –1.5V
I
CHGFET
, I
DCHFET
= –1mA
I
CHGFET
, I
DCHFET
= 1mA
V
DCIN
= V
DCDIV
= V
DCOUT
= 0V (Shutdown
Mode), V
DCIN
= V
DCDIV
= 0V (Backup Mode)
I
CHGFET
, I
DCHFET
= 1μA
C
LOAD
= 1.6nF 10% to 90%
,
C
LOAD
= 1.6nF 10% to 90%
,
l
45
100
t
IIDON
t
IIDOFF
Turn “ON”
Turn “OFF”
BATID Pin Delay Times
450
8
700
20
μs
μs
t
BIDON
t
BIDOFF
V
OHF
V
OLF
V
OLFX
Turn “ON”
Turn “OFF”
CHGFET, DCHFET High
CHGFET, DCHFET Low
CHGFET, DCHFET in Shutdown and Backup
Modes
CHGFET, DCHFET Transition Times
Rise Time
Fall Time
PWM Oscillator Switching Frequency
SafetySignal Decoder
SafetySignal Trip
(RES_COLD/RES_OR)
SafetySignal Decoder
SafetySignal Trip
(RES_IDEAL/RES_COLD)
SafetySignal Decoder
SafetySignal Trip
(RES_HOT/RES_IDEAL)
SafetySignal Decoder
SafetySignal Trip
(RES_UR/RES_HOT)
THB Pin Hot Threshold Voltage
THB Pin Hot Threshold Hysteresis Voltage
THB Pin Battery Removal Threshold Voltage
15
8
4.5
4.75
60
20
5.25
50
100
μs
μs
V
mV
mV
PWM Flyback Converter
t
R
t
F
F
PWM
SS
OR
35
15
255
300
65
65
340
ns
ns
kHz
SafetySignal Decoder and Thermistor Interface
R
THA
= 1130Ω ±1%, C
TH
= 1nF (Note 6) R
THB
l
= 54.9k ±1%.
Smart Batteries and Li-Ion Only
R
THA
= 1130Ω ±1%, C
TH
= 1nF (Note 6) R
THB
l
= 54.9k ±1%
Smart Batteries and Li-Ion Only
R
THA
= 1130Ω ±1%, C
TH
= 1nF (Note 6) R
THB
l
= 54.9k ±1%
Smart Batteries and Li-Ion Only
R
THA
= 1130Ω ±1%, C
TH
= 1nF (Note 6) R
THB
l
= 54.9k ±1%
Smart Batteries and Li-Ion Only
V
THB
Decreasing; Lead Acid Only
V
THB
Increasing; Lead Acid Only
V
THB
Increasing; Lead Acid Only
l
l
95
100
105
k
SS
CLD
28.5
30
31.5
k
SS
IDL
2.85
3
3.15
k
SS
HOT
425
0.28 •
V
THA
0.90 •
V
THA
500
0.30 •
V
THA
50
0.94 •
V
THA
575
0.36 •
V
THA
0.96 •
V
THA
Ω
V
mV
V
V
HOT
V
HOTH
V
REM
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