ZSPM4521
High-Efficiency Charger for Li-Ion
Batteries with Photovoltaic Sources
Datasheet
Brief Description
Features
•
Temperature-independent photovoltaic maximum
power tracking (MPPT) regulator
The ZSPM4521 is a DC/DC synchronous switching
lithium-ion (Li-Ion) battery charger with fully inte-
grated power switches, internal compensation, and
full fault protection. It uses a temperature-indepen-
dent photovoltaic maximum power point tracking
(MPPT) function to optimize power output from the
source during Full-Charge Constant-Current (CC)
Mode. Its switching frequency of 1MHz enables the
use of small filter components, resulting in smaller
board space and reduced bill-of material costs.
•
•
VBAT reverse-current blocking
Programmable temperature-compensated
termination voltage: 3.94V to 4.18V ± 1%
•
User programmable maximum charge current:
50mA to 1500mA
•
•
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Supervisor for VBAT reported at the NFLT pin
Input supply under-voltage lockout
Full protection for VBAT over-current, over-
temperature, VBAT over-voltage, and charging
timeout
During Full-Charge Constant-Current Mode, the duty
cycle is controlled by the MPPT regulator. Once the
battery’s termination voltage is reached, the regula-
tor operates in Constant Voltage Mode. In this mode,
the ZSPM4521 modulates the charging current until
the battery reaches full charge. When the regulator
is disabled (the EN pin is low), the device draws
10µA (typical) quiescent current (Disabled Mode).
•
•
Charge status indication
I2C™ program interface with EEPROM registers
Related IDT Smart Power Products
•
ZSPM4523 DC/DC Synchronous Switching
The ZSPM4521 includes supervisory reporting
through the NFLT (inverted fault) open-drain output
to interface other components in the system. Device
programming is achieved by an I²C™* interface
through the SCL and SDA pins.
Super Capacitor Charger With MPPT Regulator
•
•
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ZSPM4551 High-Efficiency Li-Ion Battery Charger
ZSPM4121 Ultra-low Power Under-Voltage Switch
ZSPM4141 Ultra-Low-Power Linear Regulator
Physical Characteristics
Benefits
•
•
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Wide input voltage range: 4.0V to 7.2V
Junction operating temperature: -40°C to 125°C
Package: 16-pin PQFN (4mm x 4mm)
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Up to 1.5A of continuous output current in Full-
Charge Constant Current (CC) Mode
•
High efficiency – up to 92% with typical loads
Available Support
ZSPM4521 Application Circuit
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Evaluation Kit
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Documentation
ZSPM4521
Photovoltaic Cells
VIN
VTH_REF
RREF
CIN
VTHERM
GND
VDD
CVDD
RSENSE
LOUT
Battery
SW
COUT
RTHM
SCL
SDA
VSENSE
VDD
RPULLUP
(optional)
VBAT
NFLT
VDD
RPULLUP
(optional)
EN
PGND
* I2C™ is a trademark of NXP.
© 2016 Integrated Device Technology, Inc.
1
January 27, 2016