ETC EUP8051

EUP8051
怎
Low Cost 1A Linear Battery Charge
Controllers
DESCRIPTION
FEATURES
The EUP8051 is a single Lithium-Ion (Li-Ion) and
Lithium–Polymer (Li-Pol) linear charge management
controller for use in cost sensitive and portable
applications. It combines high accuracy constant-current
and constant-voltage regulation, cell preconditioning,
temperature monitoring, automatic charge termination,
charge-status indication, in a space-saving MSOP-8
package.
The EUP8051 applies a constant current up to 1A to the
battery and the charge current can be programmed
externally with a sense-resistor.
The EUP8051 automatically terminates the charge cycle
when the charge current drops to the charge termination
threshold (ITERM) after the charge-regulation voltage is
reached.
When the input supply is removed, the EUP8051
automatically enters a low-power sleep mode, dropping
the battery drain current to less than 1µA.
A battery charge state output pin is provided to indicate
battery charge status through a display LED. The battery
charge status output is a serial interface which may also be
read by a system microcontroller.
z
z
z
Programmable Charge Current up to 1A
4.5V-7V Input Voltage Range
Ideal for Single Cell (4.1V or 4.2V) Li-Ion or
Li-Pol Batteries
z
z
z
z
Preset Charge Voltage with ±1% Accuracy
Constant-Current/Constant Voltage Operation
Preconditioning of Low Voltage Cells
Optional Cell-Temperature Monitoring Before and
During Charge
Charge Status Indication
Automatic Battery Recharge
Charge Termination by Minimum Current
Automatic Low-Power Sleep Mode When Input
Power is Removed
Available in MSOP-8 Package
RoHS Compliant and 100% Lead (Pb)-Free
DS8051 Ver 1.2 May. 2005
1
z
z
z
z
z
z
APPLICATIONS
z
z
Cellular Phones / PDAs/ MP3 Players/DSC
Handheld Instruments
EUP8051
Typical Application Circuit
DS8051 Ver 1.2 May. 2005
2
EUP8051
Pin Configurations
Part
Number
Pin
Configurations
EUP8051
MSOP-8
Pin Description
PIN
MSOP-8
I/O
VCC
1
I
Supply Voltage Input
TS
2
I
Temperature Sense Input
STAT
3
O
Charge Status Output
VSS
4
CC
5
O
FB/CE
6
I
SNS
7
I
Charge Control Output
External Feedback input or Charge Enable Function. Input from controller or
finely adjust the battery regulated voltage with external voltage divider
Current Sense Input
BAT
8
I
Battery Voltage Input
DS8051 Ver 1.2 May. 2005
DESCRIPTION
Ground
3
EUP8051
Ordering Information
Order Number
Package Type
EUP8051-41MIR1
MSOP-8
EUP8051-41MIR0
MSOP-8
EUP8051-42MIR1
MSOP-8
EUP8051-42MIR0
MSOP-8
Marking
xxxx
8051
xxxx
8051
xxxx
8051C
xxxx
8051C
EUP8051-□ □ □ □ □ □
Lead Free Code
1: Lead Free 0: Lead
Packing
R: Tape& Reel
Operating temperature range
I: Industry Standard
Package Type
M: MSOP
Output Voltage
41: 4.1V
42: 4.2V
DS8051 Ver 1.2 May. 2005
4
Operating Temperature range
-20 °C to 70°C
-20 °C to 70°C
-20 °C to 70°C
-20 °C to 70°C
EUP8051
Absolute Maximum Ratings
„
„
„
„
„
„
„
„
„
Supply voltage, (Vcc with respect to GND) ------------------------------------------------------ -0.3 to +7V
Input voltage, SNS, BAT, TS, PI (all with respect to GND)-------------------------- -0.3V to VCC +0.3V
Sink current (STAT pin) not to exceed PD -------------------------------------------------------------- 20mA
Source current (STAT pin) not to exceed PD ---------------------------------------------------------- 10mA
Output current (CC pin) not to exceed PD -------------------------------------------------------------- 40mA
Maximum Junction Temperature, TJ ------------------------------------------------------------------- 150°C
Storage temperature range, Tstg ------------------------------------------------------------- -65°C to 150°C
Lead temperature (soldering, 10s) -----------------------------------------------------------------300°C
Package Thermal Resistance, θJA- MSOP8 ---------------------------------------------------------- 80°C/W
Recommended Operating Conditions
Min.
Max.
Unit
Supply voltage, VCC
4.5
7
V
Operating free-air temperature range, TA
-20
70
°C
Electrical Characteristics over Recommended Operating Free-Air Temperature Range
EUP8051
Symbol
Parameter
Conditions
Min. Typ. Max.
I(VCC)
VCC current
I(VCCS)
VCC Sleep current
VCC=5V >VCC(min), Excluding
external loads
V(BAT) ≥ V(min),
V(BAT)-VCC ≥ 0.8V
Unit
0.6
1
mA
2
6
µA
IIB(BAT)
Input bias current on BAT pin
V(BAT)=V(REG)
1
µA
IIB(SNS)
Input bias current on SNS pin
V(SNS)=5V
1
µA
IIB(TS)
Input bias current on TS pin
V(TS)=5V
1
µA
IIB(PI)
Input bias current on PI pin
V(PI)=5V
1
µA
Battery Voltage Regulation
VO(REG)
Output voltage
DS8051 Ver 1.2 May. 2005
EUP8051-4.1
4.059
4.10
4.141
EUP8051-4.2
4.158
4.20
4.242
5
V
EUP8051
Electrical Characteristics Over Recommended Operating Free-Air Temperature Range
Symbol
V(SNS)
Parameter
Conditions
Current regulation threshold Voltage at pin SNS, relative to VCC
EUP8051
Unit
Min.
Typ. Max.
198
220
242
mV
-25
-15
-5
mV
29
30
31
58
60
62
EUP8051-4.1
2.94
3
3.06
EUP8051-4.2
3.04
3.1
3.16
Charge Termination Detection
I(TERM)
Charge termination current Voltage at pin SNS, relative to VCC
detect threshold
0°C ≤ TA ≤ 50°C
Temperature Comparator
V(TS1)
Lower temperature threshold
V(TS2)
Upper temperature threshold
TS pin voltage
%VCC
Precharge Comparator
V(min)
Precharge threshold
V
Precharge Current Regulation
I(PRECHG) Precharge current regulation
Voltage at pin SNS, relative to VCC
0°C ≤ TA ≤ 50°C
Voltage at pin SNS, relative to VCC
0°C ≤ TA ≤ 50°C , VCC=5V
15
5
15
mV
25
mV
VRCH comparator(Battery Recharge Threshold)
V(RCH)
Recharge threshold
EUP8051-4.1 and EUP8051-4.2
VOL(STAT)
Output(low)voltage
IOL=10mA
VOH(STAT)
Output(high)voltage
IOH=5mA
VOL(CC)
Output low voltage
IO(CC)=5mA(sink)
IO(CC)
Sink current
VO(REG)- VO(REG)- VO(REG)98mV 100mV 102mV
V
STAT Pin
0.5
VCC-0.5
V
CC Pin
DS8051 Ver 1.2 May. 2005
Not to exceed power rating specification(PD)
6
5
1.5
V
40
mA
EUP8051
Application Information
Functional Description
The EUP8051 is an advanced 1A linear charge controller for single Li-Ion of Li-Pol applications. Refer to Blocking
Diagram (Figure3) and Operation Flow Chart (Figure4) in this section.
DS8051 Ver 1.2 May. 2005
7
EUP8051
Power On Reset
VCC
Applied
NO
Sleep Mode
YES
Temperature
Fault
NO
Temperature
Test
TS>VTS1
TS<VTS2
YES
Preconditioning
Test
VMIN > VBAT
YES
Low Current
Conditioning
Charge
(Trickle Charge)
NO
Current
Phase Test
VREG>VBAT
YES
Constant
Current
Charging
Mode
NO
Voltage Phase
Test
IBAT>ITERM
YES
Constant
Voltage
Charging
Mode
NO
Charge
Termination
NO
Recharge Test
VRCH>VBAT
YES
Figure4. Operation Flow Chart
DS8051 Ver 1.2 May. 2005
8
EUP8051
Qualification and Precharge
When power is applied, the EUP8051 starts a
charge-cycle if a battery is already present or when a
battery is inserted. Charge qualification is based on
battery temperature and voltage.
The EUP8051 suspends charge if the battery temperature
is outside the V(TS1) to V(TS2) range and suspends charge
until the battery temperature is within the allowed range.
The EUP8051 also checks the battery voltage. If the
battery voltage is below the precharge threshold V(min),
the EUP8051 uses precharge to condition the battery. The
conditioning charge rate I(PRECHG) is set at approximately
10% of the regulation current. The conditioning current
also minimizes heat dissipation in the external
pass-element during the initial stage of charge. See
Figure5 for a typical charge-profile.
Voltage Regulation Phase
The voltage regulation feedback is through the BAT pin.
This input is tied directly to the positive side of the
battery pack. The EUP8051 monitors the battery-pack
voltage between the BAT and VSS pins. The EUP8051 is
offered in two fixed-voltage versions:4.1V, 4.2V.
FB/CE Pin Function
This pin has two functions, one is to enable/disable the
charge function, and the other is to finely adjust battery
regulation voltage. Connect this pin to VDD to enable
EUP8051, and connect to ground to disable it (Figure7).
If this pin is connected to a voltage divider as shown in
Figure8, it can be a 2.15V reference voltage to adjust the
output regulation voltage as desired.
Current Regulation Phase
The EUP8051 regulates current while the battery-pack
voltage is less than the regulation voltage, VO(REG). The
EUP8051 monitors charge current at the SNS input by
the voltage drop across a sense-resistor, RSNS, in series
with the battery pack. In current sensing configuration
(Figure6), RSNS is between the VCC and SNS pins,
charge-current feedback, applied through pin SNS,
maintains a voltage of V(SNS) across the current sense
resistor. The following formula calculates the value of the
sense resistor:
R
SNS
=
V
(SNS)
I
---------------------------- (1)
O(REG)
Where IO(REG) is the desired charging current.
Example: For 0.55A, RSNS: 0.22V/0.55A: 0.4Ω
For 1.0A, RSNS: 0.22V/1.0A: 0.22Ω
DS8051 Ver 1.2 May. 2005
9
EUP8051
For PTC Thermistors
R
R
V
= 2.15 × (1 + FB1 )V
O(REG)
R
FB2
Charge Termination and Recharge
The EUP8051 monitors the charging current during the
voltage-regulation phase. The EUP8051 declares a done
condition and terminates charge when the current drops
to the charge termination threshold, I(TERM). A new charge
cycle begins when the battery voltage falls below the
V(RCH) threshold.
Battery Temperature Monitoring
The EUP8051 continuously monitors temperature by
measuring the voltage between the TS and VSS pins. A
negative-or a positive-temperature coefficient thermistor
(NTC, PTC) and an external voltage divider typically
develop this voltage (See Figure9). The EUP8051
compares this voltage against its internal V(TS1) and V(TS2)
thresholds to determine if charging is allowed. (See
Figure10). The temperature sensing circuit is immune to
any fluctuation in VCC, since both the external voltage
divider and the internal thresholds (V(TS1) and V(TS2)) are
referenced to VCC.
The resistor values of R(T1) and R(T2) are calculated by the
following equations:
For NTC Thermistors
R
T1
T2
=
=
5× R
3 × (R
TH
TC
×R
-R
TC
TH
)
----------------------- (3)
5× R
×R
TH
TC
--------------- (4)
[(2 × (R
) - (7 × R
)]
TH
TC
DS8051 Ver 1.2 May. 2005
T2
=
5× R
3 × (R
TH
TH
5× R
×R
-R
TC
TC
)
---------------------- (5)
×R
TH
TC
[(2 × (R
) - (7 × R
)]
TH
TC
------------- (6)
Where R(TC) is the cold temperature resistance and R(TH)
is the hot temperature resistance of thermistor, as
specified by the thermistor manufacturer.
RT1 or RT2 can be omitted if only one temperature (hot or
cold) setting is required. Applying a voltage between the
V(TS1) and V(TS2) thresholds to pin TS disables the
temperature-sensing feature.
R
R
T1
=
10
EUP8051
Charge Inhibit Function
The TS pin can be used as charge-inhibit input. The user
can inhibit charge by connecting the TS pin to VCC or
VSS (or any level outside the V(TS1) to V(TS2) thresholds).
Applying a voltage between the V(TS1) and V(TS2)
thresholds to pin TS returns the charger to normal
operation.
Charge Status Indication
The EUP8051 reports the status of the charger on the
3-state STAT pin. The following table summarized the
operation of the STAT pin.
Condition
Battery conditioning and charging
Charge complete(done)
Temperature fault or sleep mode
STAT pin
High
Low
Hi-Z
The STAT pin can be used to drive a single LED
(Figure1), dual-chip LEDs (Figure2) or for interface to a
host or system processor (Figure11). When interfacing
the EUP8051 to a processor, the user can use an output
port, to recognize the high-Z state of the STAT pin. In
this configuration, the user needs to read the input pin,
toggle the output port and read the STAT pin again. In a
high-Z condition, the input port always matches the
signal level on the output port.
Selecting Input Capacitor
In most applications, all that is needed is high-frequency
decoupling capacitor. A 0.1µF ceramic, placed in
proximity to VCC and VSS pins, works well. The
EUP8051 works with both regulated and unregulated
external dc supplies. If a non-regulated supply is chosen,
the supply unit should have enough capacitance to hold
up the supply voltage to the minimum required input
voltage at maximum load. If not, more capacitance must
be added to the input of the charger.
Selecting Output Capacitor
The EUP8051 does not require any output capacitor for
loop stability.
In order to maintain good AC stability in the Constant
Voltage mode, a minimum capacitance of 10µF is
recommenced to bypass the VBAT pin to VSS. This
capacitance provides compensation when there is no
battery load. In addition, the battery and interconnections
appear inductive at high frequencies. These elements are
in the control feedback loop d>uring Constant Voltage
mode. Therefore, the bypass capacitance may be
necessary to compensate for the inductive nature of the
battery pack.
Virtually any good quality output filter capacitor can be
used, independent of the capacitor’s minimum ESR
(Effective Series Resistance) value. The actual value of
the capacitor and its associated ESR depends on the
forward transconductance (gm) and capacitance of the
external pass transistor. A 10µF tantalum or aluminum
electrolytic capacitor at the output is usually sufficient to
ensure stability for up to a 1A output current.
Selecting An External Pass-Device (PMOS or PNP)
The EUP8051 is designed to work with both P-channel
MOSFET or PNP transistor. The device should be chosen
to handle the required power dissipation, given the circuit
parameters, PCB layout and heat sink configuration. The
following examples illustrate the design process for
PMOS device:
Low-Power Sleep Mode
When the input supply is disconnected, the charger
automatically enters power-saving sleep mode.
Only consuming an ultra-low 1µA in sleep mode, the
EUP8051 minimizes battery drain when it is not
charging.
DS8051 Ver 1.2 May. 2005
11
P-Channel MOSFET
Selection steps for a P-channel MOSFET: We will use
the following conditions: VI=5V (with 10% supply
tolerance); I(REG)=1A, 4.2-V single-cell Li-Ion. VI is the
input voltage to the charger and I(REG) is the desired
charge current. (See Figure2)
EUP8051
1.
Determine the maximum power dissipation, PD , in
the transistor.
The worst case power dissipation happens when the
cell voltage, V(constant), is at its lowest (typically 3.1V
at the beginning of current regulation phase) and VI
is at its maximum. Where VD is the forward voltage
drop across the reverse-blocking diode (if one is
used), and VCS is the voltage drop across the current
sense resistor.
Determine the package size needed in order to keep
the junction temperature below the manufacturer’s
recommended value, TJMAX. Calculate the total theta,
θ(°C/W), needed.
θ
θ
JA
JA
=
=
(T
-T
)
max(J) A(max)
P
D
(150 - 40)
1.8
DS8051 Ver 1.2 May. 2005
3.
4.
5.
PD=(VI(MAX)-VD-VCS-VBAT)×IREG --------- (7)
PD=(5.5-0.4-0.2-3.1)×1A
PD=1.8W
2.
It is recommended to choose a package with a lower θJA
than the number calculated above.
--------------(8)
θJA = 61°C/W
Select a drain-source voltage, V(DS), rating greater
than the maximum input voltage. A 12V device will
be adequate in this example.
Select a device that has at least 50% higher drain
current (ID) rating than the desired charge current
I(REG).
Verify that the available drive is large enough to
supply the desired charge current.
V(GS)=(VD+V(CS)+VOL(CC))-VI(min) -------------- (9)
V(GS)=(0.4+0.2+1) - 4.5
V(GS)=-2.9
Where V(GS) is the gate-to-source voltage, VD is the
forward voltage drop across the reverse-blocking diode
(if one is used), and VCS is the voltage drop across the
current sense resistor, and VOL(CC) is the CC pin output
low voltage specification for the EUP8051.
Select a MOSFET with gate threshold voltage, V(GSth),
rating less than the calculated V(GS).
Reverse Blocking Protection
The optional reverse-blocking protection diode,
depicted in Figure1&2 provides protection from a
faulted or shorted input, or from a reversed-polarity
input source. Without the protection diode, a faulted of
shorted input would discharge the battery pack through
the body diode of the external pass transistor.
If a reverse-protection diode is incorporated in the
design, it should be chosen to handle the fast charge
current continuously at the maximum ambient
temperature. In addition, the reverse-leakage current of
the diode should be kept as small as possible.
12
EUP8051
Packaging Information
8-Pin MSOP
NOTE
1. Package body sizes exclude mold flash and gate burrs
2. Dimension L is measured in gage plane
3. Tolerance 0.10mm unless otherwise specified
4. Controlling dimension is millimeter. Converted inch dimensions are not necessarily exact.
SYMBOLS
A
A1
A2
b
C
D
E
E1
e
L
y
θ
DS8051 Ver 1.2 May. 2005
DIMENSIONS IN MILLIMETERS
MIN.
NOM.
MAX.
0.81
0.95
1.10
0.05
0.09
0.15
0.76
0.86
0.97
0.28
0.30
0.38
0.13
0.15
0.23
2.90
3.00
3.10
4.70
4.90
5.10
2.90
3.00
3.10
-----0.65
----0.40
0.53
0.66
----------0.10
0
-----6
13
DIMENSIONS IN INCHES
MIN.
NOM.
MAX.
0.032
0.0375
0.043
0.002
0.004
0.006
0.030
0.034
0.038
0.011
0.012
0.015
0.005
0.006
0.009
0.114
0.118
0.122
0.185
0.193
0.201
0.114
0.118
0.122
-----0.026
-----0.016
0.021
0.026
----------0.004
0
-----6