MAX17710BEVKIT# Maxim Integrated, MAX17710BEVKIT# Datasheet - Page 13

• 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 LDO becomes active when the AE pin is pulsed
above or held above its logic-high threshold, but the
regulator output is not immediately enabled. The device
first charges the external capacitor on PCKP. When the
voltage level on PCKP reaches 3.7V, the regulator output
is enabled in high-current mode. Powering the LDO from
PCKP instead of directly from the cell allows the device
to support large surge or startup inrush currents from the
load that the cell would be unable to handle directly.
Once in high-current mode, the AE pin can remain logic-
high or transition to an open state, and the ouput remains
active. The LDO returns to shutdown only when the AE
pin is driven below its logic-low threshold. Alternatively,
the LDO is transitioned to low-current mode by pulsing
or holding the LCE to the REG pin voltage, followed by
pulsing or holding the AE pin logic-low. Note that the
regulator transitions through a state where both high-
current and low-current modes are active at the same
time. While in low-current mode, the quiescent current
drain of the cell is reduced to 150nA, while the maximum
load current able to be supplied becomes 50FA. Similar
to the AE pin operation, the regulator remains active if the
Figure 5. Regulator Output State Diagram
Maxim Integrated
VCHG > VCE
DETECTED
CHARGE
I
QBATT
POWER-ON RESET (POR)
CHARGE CURRENT
UNDERVOLTAGE
I
I
QBATT
QBATT
SHUTDOWN
= PCKP CAPACITOR
+ 725nA (typ)
STARTUP
LOCKOUT
PCKP OFF
PCKP OFF
PCKP ON
REG OFF
REG OFF
REG OFF
= 1nA (typ)
= 1nA (typ)
Energy-Harvesting Charger and Protector
AE PULSED HIGH
STARTUP FAIL
V
AFTER 5s
PCKP
< 2.15V
V
SUCCESS
PCKP
STARTUP
> 3.7V
AE PULSED LOW
I
QBATT
AE REGULATOR
PCKP ON
ACTIVE
REG ON
= 725nA (typ)
LCE PULSED
LCE PULSED
LCE pin is open or pulled to REG, and returns to shutdown
mode when LCE is driven below its logic-low threshold.
Figure 5
If the cell and PCKP capacitance cannot provide sus-
tained support for the load, then the voltage at PCKP col-
lapses. When PCKP collapses, the system load typically
stops and allows the PCKP voltage to recover, resulting
in a perpetual retry in a futile attempt to support a load
that cannot be supported. When PCKP fails in this way,
the device shuts off the REG output to prevent futile load
retries and protect the cell from overdischarge. When the
REG output is latched off, the BATT quiescent current
reduces to 1nA (typ). Once UVLO occurs, the regulator
output remains disabled until the device detects that a
charge source has been connected to the system (V
> 4.15V).
Connecting any load to REG or PCKP instead of connect-
ing directly to the cell is highly recommended. This con-
trols the quiescent current during shutdown, enables the
device to support startup during cold, and also protects
the cell from overdischarge.
HIGH
LOW
LCE PULSED LOW
V
V
PCKP
PCKP
is the regulator output state diagram.
Figure 6
REGULATORS ACTIVE
< 2.15V (HIGH-CURRENT MODE)
< 3.0V (LOW-CURRENT MODE)
CELL UNDERVOLTAGE
I
QBATT
AE AND LCE
AFTER 500µs
PCKP ON
REG ON
= 875nA (typ)
shows the UVLO protection modes.
Cell Undervoltage Lockout (UVLO)
AE PULSED
AE PULSED
HIGH
LOW
MAX17710
I
LCE REGULATOR
QBATT
PCKP ON
ACTIVE
REG ON
= 150nA (typ)
CHG
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