Single-/Dual-Input 1-Cell Li+ Chargers with

OVP Protection and Programmable Charge Timer

6

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PIN

MAX8600

MAX8601

NAME

FUNCTION

12, 13

12, 13

DC

DC Input Supply. Connect DC to a 4.5V to 7V charging source. Bypass DC to GND with a 1µF

or larger capacitor. DC takes priority over USB when both are present (MAX8601). Both DC

inputs should be connected together externally.

14

14

FLT

Fault Status Output. FLT goes low when either the prequal timer or the fast-charge timers

expire and the battery voltage is not above the required threshold. Clear the fault by raising EN

or removing input power.

—

9

USB

USB Input Source. Connect to a USB port. Bypass USB to GND with a 1µF or larger capacitor.

—

6

USEL

USB Charge-Select Input. Logic input that determines the maximum charge current drawn

—

—

EP

Exposed Paddle. Connect to the GND plane for optimum thermal dissipation.

Pin Description (continued)

ANY STATE

FAULT

CHG = HIGH

FLT = LOW

Ω AND

Ω

Ω AND

Ω

Ω OR

Ω

Ω OR

Ω

AND VOLTAGE MODE

EN HIGH

PREQUAL

TIMEOUT

AND FAST-CHARGE

TIMEOUT

TOP-OFF

TIMEOUT

OFF

POK = HIGH, CHG = HIGH, FLT = HIGH

EN LOW AND

POWER-GOOD

PREQUAL

POK = LOW, CHG = HIGH

DONE

POK = LOW, CHG = HIGH

TOP-OFF

POK = LOW, CHG = HIGH

FAST-CHARGE

POK = LOW, CHG = LOW

THM OUT OF RANGE

POK = PREVIOUS STATE

CHG = PREVIOUS STATE

PREQUAL TIMER HELD

THM OUT OF RANGE

POK = PREVIOUS STATE

CHG = PREVIOUS STATE

FAST-CHARGE TIMER HELD

Figure 1. Charger State Diagram