MAX1535A Datasheet, PDF (1/39 Pages) Maxim Integrated Products – Highly Integrated Level 2 SMBus Battery Charger

19-2848; Rev 1; 11/03
EVAALVUAAILTAIOBNLEKIT
Highly Integrated Level 2 SMBus
Battery Charger
General Description
The MAX1535A is a highly integrated, multichemistry
battery charger that simplifies construction of advanced
smart chargers with a minimum number of external com-
ponents. It uses Intel’s system management bus
(SMBus) to control the charge voltage, charge current,
and the maximum current drawn from the AC adapter.
High efficiency is achieved through use of a constant off-
time step-down topology with synchronous rectification.
In addition to support of the Smart Battery Charger
Specifications Rev 1.1, the MAX1535A includes addi-
tional features. The maximum current drawn from the
AC adapter is programmable to avoid overloads when
supplying the load and the battery charger simultane-
ously. This enables the user to reduce the cost of the
AC adapter. The MAX1535A provides a digital output
that indicates the presence of an AC adapter. Based on
the presence or absence of the AC adapter, the
MAX1535A automatically selects the appropriate
source for supplying power to the system by controlling
two external P-channel MOSFETs. Under system con-
trol, the MAX1535A allows the battery to undergo a
relearning or conditioning cycle in which the battery is
completely discharged through the system load and
then recharged.
The MAX1535A is capable of charging 2, 3, or 4 lithium-
ion (Li+) cells in series, providing charge currents as
high as 8A. The DC-to-DC converter in the MAX1535A
uses a high-side P-channel switch with an N-channel
synchronous rectifier. The charge current and input cur-
rent-limit sense amplifiers have low input-offset errors
and can use small-value sense resistors (0.01Ω, typ).
The MAX1535A is available in a 5mm x 5mm 32-pin thin
QFN package and operates over the extended -40°C to
+85°C temperature range. An evaluation kit is available
to reduce design time.
Applications
Notebook and Subnotebook Computers
Tablet PCs
Portable Equipment with Rechargeable Batteries
Features
♦ Compliant with Level 2 Smart Battery Charger
Specifications Rev 1.1
♦ Intel SMBus 2-Wire Serial Interface
♦ ±0.5% Charge-Voltage Accuracy
♦ 11-Bit Charge-Voltage Resolution
♦ ±3% Input Current-Limit Accuracy
♦ Uses Small (10mΩ) Current-Sense Resistors
♦ 8A Maximum Charge Current
♦ 6-Bit Input and Charge-Current Resolution
♦ 8V to 28V Input Voltage Range
♦ 175s Charge Safety Timer
♦ Automatic Selection of System Power Source
♦ Charges any Battery Chemistry (Li+, NiCd, NiMH,
Lead Acid, etc.)
Ordering Information
PART
TEMP RANGE PIN-PACKAGE
MAX1535AETJ -40°C to +85°C 32 Thin QFN (5mm x 5mm)
TOP VIEW
Pin Configuration
32 31 30 29 28 27 26 25
DCIN 1
LDO 2
ACIN 3
REF 4
GND 5
CCS 6
CCI 7
CCV 8
MAX1535A
24 DLOV
23 DLO
22 PGND
21 CSIP
20 CSIN
19 BATT
18 GND
17 I.C.
9 10 11 12 13 14 15 16
THIN QFN (5mm x 5mm)
________________________________________________________________ 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.