MAX17085BETL+ Maxim Integrated Products, MAX17085BETL+ Datasheet - Page 21

• Manufacturer Part Number: MAX17085BETL+
• Description: Battery Management Dual Main Step-Down Controller
• Manufacturer: Maxim Integrated Products

Specifications of MAX17085BETL+

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

The MAX17085B features a thermal fault-protection cir-
cuit. When the junction temperature rises above +160NC,
a thermal sensor activates the fault latch, pulls PGOOD
low, enables the 20I discharge circuit, and disables
the controller—DH and DL pulled low. After the junction
temperature cools by 50NC, the controller automatically
restarts. This protects the internal LDO when a sustained
overcurrent or output short circuit occurs.
When V
old, the MAX17085B clears the fault latches and resets
the soft-start circuit, preparing the controller for power-up.
However, the V
inhibits switching until V
threshold.
Figure 2. Functional Diagram
CC
rises above the power-on reset (POR) thresh-
Thermal-Fault Protection (t
Integrated Charger, Dual Main Step-Down
CC
______________________________________________________________________________________
undervoltage-lockout (UVLO) circuitry
IINP
BATT
DHC
BSTC
LXC
DLC
CC
CSIP
CSIN
ISET
VCTL
CELLS
ACIN
ACOK
V
REF
GND
CC
CC
Controllers, and Dual LDO Regulators
reaches its 4.2V (typ) UVLO
LDO5
CURRENT-
DRIVER
VBATT
COMP
SENSE
BLOCK
AMP
REF
TOFF
AC
CSSP
SENSE AMP
CURRENT-
ACOV
POR, UVLO
BLOCK
CSSN
LVC
SHDN
)
MAX17085B
ACOV
CHARGE
PUMP
PAD
When V
edge), the controller stops switching, pulling DH and
DL low. When the 1.5V POR falling edge threshold is
reached, the DL state no longer matters since there is
not enough voltage to force the switching MOSFETs
into a low on-resistance state, so the controller pulls DL
high, allowing a soft discharge of the output capaci-
tors (damped response). However, if the V
before reaching the falling POR threshold, DL remains
low until the error comparator has been properly pow-
ered up and triggers an on-time.
When DCIN is high enough for LDO5 to be in regulation
and V
running. Charger operation requires DCIN to be above its
7.7V UVLO threshold.
DCIN
PDSL
SKIP
CC
CC
to be above its UVLO, the main SMPS can begin
TON ADJUST
BLOCK
drops below the UVLO threshold (falling
TON
OUT5
OUT3
SMPS3 DRIVER
LDO5
SKIP
BLOCK
REF
OUT5
DRIVER
LDO3
LDO5
FB
PGOOD
LOGIC
PGOOD
ILIM3
ILIM5
OUT3
LDO3
LDO5
OUT5
BST3
DCIN
BST5
SKIP
ON3
DH3
TON
ON5
DH5
DL5
LX3
DL3
LX5
CC
recovers
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