MAX1645 Datasheet, PDF (1/32 Pages) Maxim Integrated Products – Advanced Chemistry-Independent, Level 2 Battery Chargers with Input Current Limiting

19-1566; Rev 2; 1/01
Advanced Chemistry-Independent, Level 2
Battery Chargers with Input Current Limiting
General Description
The MAX1645 are high-efficiency battery chargers capa-
ble of charging batteries of any chemistry type. It uses the
Intel System Management Bus (SMBus) to control volt-
age and current charge outputs.
When charging lithium-ion (Li+) batteries, the MAX1645
automatically transition from regulating current to regu-
lating voltage. The MAX1645 can also limit line input
current so as not to exceed a predetermined current
drawn from the DC source. A 175s charge safety timer
prevents “runaway charging” should the MAX1645 stop
receiving charging voltage/ current commands.
The MAX1645 employs a next-generation synchronous
buck control circuity that lowers the minimum input-to-
output voltage drop by allowing the duty cycle to
exceed 99%. The MAX1645 can easily charge one to
four series Li+ cells.
Applications
Notebook Computers
Point-of-Sale Terminals
Personal Digital Assistants
Features
o Input Current Limiting
o 175s Charge Safety Timeout
o 128mA Wake-Up Charge
o Charges Any Chemistry Battery: Li+, NiCd,
NiMH, Lead Acid, etc.
o Intel SMBus 2-Wire Serial Interface
o Compliant with Level 2 Smart Battery Charger
Spec Rev. 1.0
o +8V to +28V Input Voltage Range
o Up to 18.4V Battery Voltage
o 11-Bit Battery Voltage Setting
o ±0.8% Output Voltage Accuracy with Internal
Reference
o 3A max Battery Charge Current
o 6-Bit Charge Current Setting
o 99.99% max Duty Cycle for Low-Dropout Operation
o Load/Source Switchover Drivers
o >97% Efficiency
TOP VIEW
Pin Configuration
DCIN 1
LDO 2
CLS 3
REF 4
CCS 5
CCI 6
CCV 7
GND 8
BATT 9
DAC 10
V_DD 11
THM 12
SCL 13
SDA 14
MAX1645
MAX1645A
QSOP
28 CVS
27 PDS
26 CSSP
25 CSSN
24 BST
23 DHI
22 LX
21 DLOV
20 DLO
19 PGND
18 CSIP
17 CSIN
16 PDL
15 INT
PART
MAX1645EEI
MAX1645AEEI
Ordering Information
TEMP. RANGE
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
28 QSOP
28 QSOP
Typical Operating Circuit appears at end of data sheet.
SMBus is a trademark of Intel Corp.
________________________________________________________________ Maxim Integrated Products 1
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