|
|
PDF MAX1879 Data sheet ( Hoja de datos )
| Número de pieza | MAX1879 | |
| Descripción | Simple / Efficient / 1-Cell Li+ Pulse Charger | |
| Fabricantes | Maxim Integrated | |
| Logotipo |  |
|
Hay una vista previa y un enlace de descarga de MAX1879 (archivo pdf) en la parte inferior de esta página. Total 11 Páginas | ||
|
No Preview Available !
19-2061;
Rev
0; 5/01
EVALUATION
KIT
AVAILABLE
Simple, Efficient, 1-Cell Li+ Pulse Charger
General Description
The MAX1879 single-cell lithium-ion (Li+) battery charger
utilizes an efficient pulse-charging architecture to minimize
power dissipation in portable devices. This architecture
combines the efficiency of switch-mode chargers with the
simplicity and low cost of linear chargers. This simple
device, in conjunction with a current-limited wall cube and
a PMOS transistor, allows safe and fast charging of a sin-
gle Li+ cell.
The MAX1879 initiates charging in one of three ways: bat-
tery insertion, charger power-up, or toggling the THERM
pin. Key safety features include continuous voltage and
temperature monitoring, a preset charger time-out, and an
8mA precharge current mode to charge near-dead cells.
Automatic detection of input power removal shuts down
the device, minimizing current drain from the battery. An
overall system accuracy of 0.75% ensures that the cell
capacity is fully utilized without cycle life degradation.
The MAX1879 is offered in a space-saving 8-pin µMAX
package. An evaluation kit (MAX1879EVKIT) is available
to help reduce design time.
Applications
Single-Cell Li+ Powered Portables
Self-Charging Battery Packs
PDAs
Cell Phones
Cradle Chargers
Features
o Simple Design Minimizes Heat
o Low Component Count, No Inductor
o Battery-Full Indicator
o 0.75% Accurate Battery Regulation
o 1.5µA (max) Battery Current Drain with Wall Cube
Removed
o Restart Charging at 4.0V
o Continuous Overvoltage and Overtemperature
Protection
o Safely Precharges Near-Dead Cells
o Automatic Power-Down when Power Source is
Removed
o Charges 1 Cell from as Low as 4.5V
o Pin-Compatible Upgrade to MAX1679
PART
MAX1879EUA
Ordering Information
TEMP. RANGE
-40°C to +85°C
PIN-PACKAGE
8-µMAX
TOP VIEW
Pin Configuration
IN 1
GATE 2
CHG 3
TSEL 4
MAX1879
8 BATT
7 THERM
6 GND
5 ADJ
µMAX
Typical Operating Circuit
CURRENT-
LIMITED
AC WALL
ADAPTER
LED
PULSE WIDTH
SELECT INPUT
IN GATE
CHG BATT
MAX1879
TSEL GND
THERM
ADJ
THERMISTOR
1-CELL
Li+
BATTERY
________________________________________________________________ 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 page  
Simple, Efficient, 1-Cell Li+ Pulse Charger
Typical Operating Characteristics
(VIN = CHG = +10V, VBATT = +4.2V, THERM = 10kΩ to GND, TA = +25°C, unless otherwise noted.)
NORMALIZED TIMER PERIOD
vs. AMBIENT TEMPERATURE
1.020
1.015
NORMALIZED TO +25°C
1.010
1.005
1.000
0.995
0.990
0.985
0.980
-40
-20
0 20 40 60
TEMPERATURE (°C)
80
1.0020
1.0015
NORMALIZED BATTERY REGULATION
VOLTAGE vs. TEMPERATURE
NORMALIZED TO +25°C
1.0010
1.0005
1.0000
0.9995
0.9990
0.9985
0.9980
0.9975
0.9970
-40 -20
0 20 40 60 80
TEMPERATURE (°C)
9.0
8.8
8.6
8.4
8.2
8.0
7.8
7.6
7.4
7.2
7.0
5
PRECHARGE CURRENT
vs. INPUT VOLTAGE
VBATT = 0
VBATT = 2V
10 15 20
VIN (V)
25
Pin Description
PIN NAME
FUNCTION
1 IN Input Voltage from Current-Limited Voltage Source (+22V max). Bypass to GND with a 0.1µF capacitor.
2 GATE Gate Drive for External PMOS Pass Element. The PMOS device should have a VGS threshold less than
2.5V. See Selecting External Components.
Charge Status Indication. A CHG low indicates that the MAX1879 is charging a battery. CHG goes high
when the on/off duty cycle falls to 1/8, indicating that the battery is charged to approximately 95% of full
3 CHG capacity. CHG is an open-drain current-limited N-channel MOSFET suitable for directly driving an LED.
Connect a pullup resistor to the logic supply to generate a logic-level signal. CHG blinks at 2Hz during the
Prequalification state (2.2V < VBATT < 2.5V) and during a temperature fault.
4 TSEL Minimum ON/OFF Pulse Width Selection (Table 2)
Battery Regulation Voltage Adjustment. Bypass to GND with a 1000pF capacitor. Connect a resistor from
5 ADJ ADJ to GND to reduce the nominal +4.200V regulation set point. See Adjusting the Battery Regulation
Voltage.
6 GND Ground. See Layout Guidelines for information on system grounding. Connect the battery’s negative
terminal to GND.
Thermistor Temperature-Sensor Input. Connect an NTC thermistor (10kΩ at +25°C) from THERM to GND to
7 THERM allow prequalification of the cell temperature for fast-charge. Replace the thermistor with a 10kΩ resistor if
temperature sensing is not required.
Cell Voltage Monitor Input, Precharge Current Output, and MAX1879 Power Source. Connect BATT to the
8 BATT positive terminal of a single Li+ cell. Bypass BATT with a capacitor to ground (1.5µF per amp of charge
current).
_______________________________________________________________________________________ 5
5 Page 
Simple, Efficient, 1-Cell Li+ Pulse Charger
Package Information
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 11
© 2001 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
11 Page | ||
| Páginas | Total 11 Páginas | |
| PDF Descargar | [ Datasheet MAX1879.PDF ] | |
Hoja de datos destacado
| Número de pieza | Descripción | Fabricantes |
| MAX187 | +5V / Low-Power / 12-Bit Serial ADCs | Maxim Integrated |
| MAX1870A | Step-Up / Step-Down Li+ Battery Charger | Maxim Integrated |
| MAX1873 | Simple Current-Limited Switch-Mode Li Charger Controller | Maxim Integrated |
| MAX1874 | Dual-Input / USB/AC Adapter / 1-Cell Li+ Charger with OVP and Thermal Regulation | Maxim Integrated |
| Número de pieza | Descripción | Fabricantes |
| SLA6805M | High Voltage 3 phase Motor Driver IC. |
 Sanken |
| SDC1742 | 12- and 14-Bit Hybrid Synchro / Resolver-to-Digital Converters. |
 Analog Devices |
|
DataSheet.es es una pagina web que funciona como un repositorio de manuales o hoja de datos de muchos de los productos más populares, |
| DataSheet.es | 2020 | Privacy Policy | Contacto | Buscar |