19-0781; Rev 0; 4/07
1.5A Dual-Input USB/AC Adapter Charger
and Smart Power Selector
General Description
The MAX8677C is an integrated 1-cell Li+ charger and
Smart Power Selector™ with dual (DC and USB) power
inputs. It can operate with either separate inputs for
USB and AC adapter power*, or from a single input that
accepts both. All power switches for charging and
switching the load between battery and external power
are included on-chip. No external MOSFETs are
required.
The MAX8677C features a Smart Power Selector to
make the best use of limited USB or adapter power.
The battery charge current and input current limit are
independently set up to 1.5A and 2A, respectively.
Input power not used by the system charges the bat-
tery. USB input current can be set to 100mA or 500mA.
Automatic input selection switches the system load
from battery to external power.
Other features include overvoltage protection (OVP),
charge status and fault outputs, power-OK monitors,
charge timer, and battery thermistor monitor.
Additionally, on-chip thermal limiting reduces the battery
charge rate to prevent overheating. The MAX8677C is
available in a 4mm x 4mm, 24-pin TQFN-EP package.
o
No External MOSFETs Required
o
Common or Separate USB and Adapter Inputs
o
System Operates with Discharged or No Battery
o
Automatic Adapter/USB/Battery Switchover
o
Load Peaks Over Adapter Rating Are Supported
by Battery
o
Input Overvoltage Protection to 16V
o
40mΩ System-to-Battery Switch
o
Thermal Regulation Prevents Overheating
o
PREQ, CHG, DOK, UOK,
and
FLT
Indicators
o
4.35V (typ) SYS Regulation Voltage
Features
o
Complete Charger and Smart Power Selector
MAX8677C
Ordering Information
PART
MAX8677CETG+
TEMP RANGE
-40°C to +85°C
PIN-
PACKAGE
24 TQFN-EP**
(4mm x 4mm)
PKG
CODE
T2444-4
Applications
PDAs, Palmtops, and Wireless Handhelds
Smart Cell Phones
Portable Media/MP3 Players
GPS Navigation
Digital Cameras
+Denotes
a lead-free package.
**EP
= Exposed paddle.
Pin Configuration
18
17
16
15
14
13
12 THM
11 ISET
10 CT
USUS
9 GND
8 VL
7 PSET
1
PREQ
2
DC
3
DC
4
CEN
5
PEN1
6
PEN2
TSET
USB
USB
BAT
CHG 19
SYS 20
SYS 21
BAT
Typical Operating Circuit
AC
ADAPTER
DC
Q1
MAX8677C
CHARGE
CURRENT
SYS
LOAD
CURRENT
DOK 22
SYSTEM
LOAD
MAX8677C
UOK 23
FLT 24
USB
USB
Q2
Q3
CHARGE AND
SYS LOAD
SWITCH
BAT
BATTERY
GND
TQFN
(4mm x 4mm x 0.8mm)
Smart Power Selector is a trademark of Maxim Integrated
Products, Inc.
*Protected
by U.S. Patent #6,507,172.
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1.5A Dual-Input USB/AC Adapter Charger
and Smart Power Selector
MAX8677C
ABSOLUTE MAXIMUM RATINGS
DC, PEN1 to GND .................................................-0.3V to +16V
USB to GND .............................................................-0.3V to +9V
VL to GND ................................................................-0.3V to +4V
BAT, SYS,
CEN,
USUS, PEN2, TSET to GND...........-0.3V to +6V
THM, PSET, ISET, CT to GND .........................-0.3V to VL + 0.3V
PREQ, CHG, DOK, UOK, FLT
to GND .....................-0.3V to +6V
EP (exposed paddle) to GND ...............................-0.3V to +0.3V
DC Continuous Current (total in 2 pins) .........................2.4A
RMS
SYS Continuous Current (total in 2 pins) ........................2.4A
RMS
USB Continuous Current (total in 2 pins) .......................2.0A
RMS
BAT Continuous Current (total in 2 pins)........................2.4A
RMS
Continuous Power Dissipation (T
A
= +70°C)
(derate 27.8mW/°C above +70°C) ........................... 2222mW
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature Range ............................-40°C to +125°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(V
DC
= 5V, THM =
CEN
= USUS = GND, V
BAT
= 4V, V
PEN1
= V
PEN2
= 5V, USB, TSET,
PREQ, CHG, DOK, UOK, FLT
are unconnected,
T
A
= -40°C to +85°C, unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 1)
PARAMETER
DC-TO-SYS PREREGULATOR
DC Operating Range
DC Standoff Voltage
DC Undervoltage Threshold
DC Overvoltage Threshold
DC Supply Current
DC Shutdown Current
DC-to-SYS On-Resistance
DC-to-BAT Dropout Voltage
V
BAT
= V
SYS
= 0V
When V
DOK
goes low, V
DC
rising, 500mV typical hysteresis
When V
DOK
goes high, V
DC
rising, 360mV typical hysteresis
I
SYS
= I
BAT
= 0mA, V
CEN
= 0V
I
SYS
= I
BAT
= 0mA, V
CEN
= 5V
V
DC
= V
CEN
= USUS = 5V, V
PEN1
= 0V
I
SYS
= 400mA, V
CEN
= 5V
When SYS regulation and charging stops, V
DC
falling,
150mV hysteresis
R
PSET
= 1.5kΩ
R
PSET
= 3kΩ
DC Current Limit
(See Table 2 for Input Source
Control)
V
DC
= 6V, V
SYS
= 5V,
T
A
= +25°C
R
PSET
= 6.3kΩ
V
PEN1
= 0V, V
PEN2
= 5V
(500mA USB mode)
V
PEN1
= 0V, V
PEN2
= 0V
(100mA USB mode)
PSET Resistance Range
SYS Regulation Voltage
Input Current Soft-Start Time
Thermal-Limit Temperature
Thermal-Limit Gain
VL Voltage
V
DC
= 6V, I
SYS
= 1mA to 1.75A, V
CEN
= 5V
Connecting DC when no USB present
Connecting DC with USB present
Die temperature at which charging and input current limits
are reduced
I
SYS
reduction/die temperature (above +100°C)
I
VL
= 0 to 10mA
3.0
10
1800
900
450
450
80
1.5
4.29
4.35
1.5
50
+100
5
3.3
3.6
3.95
6.8
4.0
6.9
1
0.8
195
0.2
50
2000
1000
475
475
95
4.1
6.6
14
4.05
7.0
2
1.5
333
0.35
90
2200
1100
500
500
100
6.3
4.40
kΩ
V
ms
µs
°C
%/°C
V
mA
V
V
V
V
mA
µA
Ω
mV
CONDITIONS
MIN
TYP
MAX
UNITS
2
_______________________________________________________________________________________
1.5A Dual-Input USB/AC Adapter Charger
and Smart Power Selector
ELECTRICAL CHARACTERISTICS (continued)
(V
DC
= 5V, THM =
CEN
= USUS = GND, V
BAT
= 4V, V
PEN1
= V
PEN2
= 5V, USB, TSET,
PREQ, CHG, DOK, UOK, FLT
are unconnected,
T
A
= -40°C to +85°C, unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 1)
PARAMETER
USB-TO-SYS PREREGULATOR
USB Operating Range
USB Standoff Voltage
USB Undervoltage Threshold
USB Overvoltage Threshold
USB Supply Current
USB Shutdown Current
USB-to-SYS On-Resistance
USB-to-BAT Drop-Out Voltage
V
BAT
= V
SYS
= 0V
When V
UOK
goes low, V
USB
rising, 500mV hysteresis
When V
UOK
goes high, V
USB
rising, 100mV hysteresis
I
SYS
= I
BAT
= 0mA, V
CEN
= 0V, V
PEN2
= 0V
I
SYS
= I
BAT
= 0mA, V
CEN
= 5V, V
PEN2
= 0V
DC = unconnected, V
USB
= V
CEN
= V
USUS
= 5V
DC = unconnected, V
USB
= V
CEN
= 5V, I
SYS
= 400mA
When SYS regulation and charging stops, V
USB
falling,
250mV hysteresis
DC = unconnected,
V
USB
= 5V,
T
A
= +25°C
V
PEN1
= 0V,
V
PEN2
= 5V
V
PEN1
= 0V,
V
PEN2
= 0V
10
450
80
4.29
3.95
6.8
4.0
6.9
1
0.9
190
0.2
50
475
95
4.35
50
+100
I
SYS
reduction/die temperature (above +100°C)
DC = unconnected, V
USB
= 5V; I
VL
= 0 to 10mA
V
DC
= 0V, V
BAT
= 4.2V, I
SYS
= 1A
V
PEN1
= V
PEN2
= 0V, I
SYS
= 200mA
I
BAT
= 0mA
T
A
= +25°C
T
A
= 0°C to +85°C
40
4.179
4.158
-135
0.3
R
ISET
= 2.4kΩ
R
ISET
= 4kΩ
R
ISET
= 10kΩ
BAT Charge-Current Accuracy,
Charger Loop in Control
V
SYS
= 5.5V,
T
A
= 0°C to +85°C
R
ISET
= 4kΩ, V
BAT
= 2.5V
(prequal mode)
R
ISET
= 6.2kΩ, V
BAT
= 2.5V
(prequal mode)
R
ISET
= 10kΩ, V
BAT
= 2.5V
(prequal mode)
1125
675
270
50
23
1250
750
300
75.0
48
30
3.0
5
3.3
0.04
68
4.2
4.2
-95
3.6
0.08
90
4.221
4.242
-45
1.5
1375
825
330
100
73
mA
4.1
6.6
8
4.05
7.0
2
1.5
333
0.31
90
500
mA
100
4.40
V
µs
°C
%/°C
V
Ω
mV
V
mV
A
V
V
V
V
mA
µA
Ω
mV
CONDITIONS
MIN
TYP
MAX
UNITS
MAX8677C
USB Current Limit
(See Table 2 for Input Source
Control)
SYS Regulation Voltage
Input Limiter Soft-Start Time
Thermal-Limit Start Temperature
Thermal-Limit Gain
VL Voltage
CHARGER
BAT-to-SYS On-Resistance
BAT-to-SYS Reverse Regulation
Voltage
BAT Regulation Voltage
BAT Recharge Threshold
BAT Charge-Current Set Range
DC = unconnected, V
USB
= 6V;
I
SYS
= 1mA to 400mA, V
CEN
= 5V
Input current ramp time
Change in V
BAT
from DONE to fast-charge
R
ISET
= 10kΩ to 2kΩ (Note 2)
_______________________________________________________________________________________
3
1.5A Dual-Input USB/AC Adapter Charger
and Smart Power Selector
MAX8677C
ELECTRICAL CHARACTERISTICS (continued)
(V
DC
= 5V, THM =
CEN
= USUS = GND, V
BAT
= 4V, V
PEN1
= V
PEN2
= 5V, USB, TSET,
PREQ, CHG, DOK, UOK, FLT
are unconnected,
T
A
= -40°C to +85°C, unless otherwise noted. Typical values are at T
A
= +25°C.) (Note 1)
PARAMETER
ISET Voltage
Charger Soft-Start Time
BAT Prequal Threshold
BAT Leakage Current
DONE Threshold as a
Percentage of Fast-Charge
Maximum Prequal Time
Maximum Fast-Charge Time
Timer Accuracy
Timer Extend Threshold
Timer Suspend Threshold
THM
THM Threshold, Cold
THM Threshold, Hot
THM Threshold, Disabled
THM Input Leakage
When charging is suspended, 2% hysteresis
When charging is suspended, 2% hysteresis
When THM function is disabled
THM = GND or V
L
; T
A
= +25°C
THM = GND or V
L
; T
A
= +85°C
High level
Logic Input Thresholds
Low level
Hysteresis
High level
TSET Input Threshold
Midlevel
Low level
TSET Input-Bias Current
Logic Input-Leakage Current
Logic Output Voltage, Low
Logic Output-Leakage Current,
High
TSET = GND
TSET = V
L
V
INPUT
= 0 to 5.5V
Sinking 1mA
V
OUT
= 5.5V
T
A
= +25°C
T
A
= +85°C
T
A
= +25°C
T
A
= +85°C
-20
-6
6
0.001
0.01
25
0.001
0.01
100
1
20
1
V
L
- 0.3
1.2
V
L
- 1.2
0.3
µA
µA
mV
µA
V
50
1.3
0.4
-0.1
72
26
74
28
3
0.001
0.01
+0.2
76
30
% of V
L
% of V
L
% of V
L
µA
CONDITIONS
R
ISET
= 4kΩ, I
BAT
= 500mA
(V
ISET
= 1.5V at full charge current)
Charge-current ramp time
V
BAT
rising, 180mV hysteresis
V
BAT
= 4.2V
No DC or USB power connected
DC or USB connected, V
CEN
= 5V
V
TSET
= 0
I
BAT
decreasing
V
TSET
= open
V
TSET
= V
L
From V
CEN
falling to end of prequal charge,
V
BAT
= 2.5V, C
T
= 0.068µF
From V
CEN
falling to V
FLT
falling, C
T
= 0.068µF
C
T
= 0.068µF
Percentage of fast-charge current below which timer
clock operates at half speed
Percentage of fast-charge current below which timer
clock pauses
-20
50
20
2.9
MIN
0.9
TYP
1.0
1.5
3
3
3
5
10
15
30
300
+20
Min
Min
%
%
%
%
3.1
6
6
MAX
1.1
UNITS
V
ms
V
µA
LOGIC I/O:
CHG, FLT, PREQ, DOK, UOK,
PEN1, PEN2,
CEN,
TSET, USUS
V
mV
Note 1:
Limits are 100% production tested at T
A
= +25°C. Limits over the operating temperature range are guaranteed by design.
Note 2:
Guaranteed by design.
4
_______________________________________________________________________________________
1.5A Dual-Input USB/AC Adapter Charger
and Smart Power Selector
Typical Operating Characteristics
(T
A
= +25°C, unless otherwise noted.)
USB QUIESCENT CURRENT
vs. USB VOLTAGE (CHARGER ENABLED)
MAX8677C toc01
MAX8677C
USB QUIESCENT CURRENT
vs. USB VOLTAGE (CHARGER DISABLED)
MAX8677C toc02
USB QUIESCENT CURRENT
vs. USB VOLTAGE (SUSPEND)
V
BAT
= 4.2, USUS = 1
USB QUIESCENT CURRENT (mA)
0.35
0.30
0.25
0.20
0.15
0.10
0.05
0
PEN1 = X, PEN2 = 1
MAX8677C toc03
1.0
0.9
USB QUIESCENT CURRENT (mA)
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
0
1
2
3
EXITING UVLO
4
5
6
7
8
USB VOLTAGE (V)
ENTERING OVLO
V
BAT
= 4.2, V
USUS
= 0V
CHARGER IN
DONE MODE
I
SYS
= 0V
PEN1 = X, PEN2 = 1
V
USB
RISING
V
USB
FALLING
1.2
V
BAT
= 4.2, V
USUS
= 0V
USB QUIESCENT CURRENT (mA)
1.0
0.8
0.6
0.4
0.2
0
0
1
2
3
ENTERING OVLO
EXITING UVLO
4
5
6
7
8
USB VOLTAGE (V)
CEN = 1
I
SYS
= 0V
PEN1 = X, PEN2 = 1
V
USB
RISING
V
USB
FALLING
0.40
0
1
2
3
4
5
6
7
8
USB VOLTAGE (V)
BATTERY LEAKAGE CURRENT
vs. BATTERY VOLTAGE (USB DISCONNECTED)
MAX8677C toc04
BATTERY LEAKAGE CURRENT
vs. TEMPERATURE
MAX8677C toc05
BATTERY LEAKAGE CURRENT
vs. BATTERY VOLTAGE (USB CONNECTED)
V
USB
= 5V
USUS = 1
CEN = 1
MAX8677C toc06
4.0
USB = OPEN
BATTERY LEAKAGE CURRENT (μA)
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
0
1
2
3
4
5
BATTERY VOLTAGE (V)
3.60
V
BAT
= 4V
BATTERY LEAKAGE CURRENT (μA)
3.58
3.56
3.54
3.52
3.50
3.48
3.46
-40
-15
10
35
60
7
BATTERY LEAKAGE CURRENT (μA)
6
5
4
3
2
1
0
85
0
1
2
3
4
5
TEMPERATURE (°C)
BATTERY VOLTAGE (V)
CHARGE CURRENT
vs. BATTERY VOLTAGE (100mA USB)
MAX8677C toc07
CHARGE CURRENT
vs. BATTERY VOLTAGE (500mA USB)
MAX8677C toc08
CHARGE CURRENT
vs. BATTERY VOLTAGE (1ADC)
V
DC
= 5V
PEN1 = 1 , PEN2 = X
V
BAT
RISING
V
BAT
FALLING
MAX8677C toc09
100
90
80
CHARGE CURRENT (mA)
70
60
50
40
30
20
10
0
0
1
2
3
4
5
BATTERY VOLTAGE (V)
V
USB
= 5V
PEN1 = X , PEN2 = 1
V
BAT
RISING
V
BAT
FALLING
500
450
400
CHARGE CURRENT (mA)
350
300
250
200
150
100
50
0
0
V
USB
= 5V
PEN1 = X, PEN2 = 1
V
BAT
RISING
V
BAT
FALLING
1.2
1.0
CHARGE CURRENT (A)
0.8
0.6
0.4
0.2
0
1
2
3
4
5
0
1
2
3
4
5
BATTERY VOLTAGE (V)
BATTERY VOLTAGE (V)
_______________________________________________________________________________________
5
下载中心专版
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
