MAX17710BEVKIT# Maxim Integrated, MAX17710BEVKIT# Datasheet - Page 9

• Manufacturer Part Number: MAX17710BEVKIT#
• Description: Power Management IC Development Tools
• Manufacturer: Maxim Integrated
• Type: Energy Harvestingr
• Series: MAX17710r

Specifications of MAX17710BEVKIT#

• Product: Power Management Development Tools
• Tool Is For Evaluation Of: MAX17710
• Output Voltage: 1.8 V, 2.3 V, 3.3 V
• Output Current: 625 nA
• Part # Aliases: 90-NC01K#B00

The MAX17710 controls two main functions related to man-
agement of an energy-harvesting application: charging a
low-capacity cell with overcharge protection and an LDO
regulator output with overdischarge protection. With the
exception of protection features, charging and regulation
functions operate completely independently of one another.
Initial power-up of the device occurs when a cell is con-
nected to the BATT pin. In this state, the device pulls only
1nA (typ) from the cell and LDO functions are disabled. Only
after a charger has been applied and V
4.15V (V
allow discharging.
The device charges the cell from an external energy
source connected to the CHG pin. Whenever the volt-
age on CHG is greater than the voltage on BATT, the
energy-harvesting circuit directly passes current to the
cell without any interaction from the device. When CHG
rises above V
the charging voltage to 4.125V and protects the cell from
overcharge. Also at this time, any UVLO is reset, allow-
ing the LDO to power the application load. This release
of the lockout is latched by CHG exceeding V
Figure 1. Typical Application Charge Circuit Harvesting from High-Voltage Charge Sources
Maxim Integrated
CE
) does the device initialize to full operation and
CE
, the input linear regulator turns on to limit
CHARGING SOURCE
HIGH-VOLTAGE AC
Charge-Regulator Operation
(SOLAR, PIEZO)
Energy-Harvesting Charger and Protector
THINERGY
MEC101
Detailed Description
CHARGING SOURCE
HIGH-VOLTAGE DC
(SOLAR, PIEZO)
CHG
Operation
0.22µF
rises above
CE
and
BATT
SEL2
SEL1
CHG
LX
FB
GND
remains active after the removal of the charge voltage.
The state of this latch is off when initial power is applied
to the BATT pin.
While charging, the device consumes approximately
625nA from the CHG source until the voltage on CHG
exceeds 4.15V. Above 4.15V, the IC enters dropout and
BATT quiescent current increases from 1nA to 450nA.
Whenever a harvest source pulls the CHG pin above
5.3V, an internal shunt regulator enables a path to GND
to limit the voltage at the CHG pin. The internal shunt
path can sustain currents up to 50mA. If it is possible for
the harvest source to exceed this power limit, an external
protection circuit is required to prevent damage to the
device.
cuit harvesting from high-voltage charge sources. Note
that a 0.22FF on CHG is recommended for shunt stability
when charging from high-voltage sources.
In the application circuit example, the cell is charged by
several high-voltage harvest sources. Whenever either har-
vest source voltage is higher than the cell voltage, charge
is transferred directly. If either charge source exceeds
4.15V, the device begins to limit current flow to regulate the
cell’s voltage to 4.125V. If either charge source exceeds
5.3V, the internal CHG shunt discharges up to 50mA
through the device to GND to protect the CHG pin.
EP
MAX17710
PGND
Figure 1
PCKP
REG
LCE
AE
10µF
shows the typical application charge cir-
1µF
MICROCONTROLLER
LOAD V
MECHANICAL,
DETECTOR
RF, PIEZO,
OR OTHER
LOAD V
EVENT
DD
MAX17710
DD
CHG Shunt
9