DS2720

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POWER MODES

The DS2720 has two power modes: active and sleep. While in active mode, the DS2720 continuously

performs safety monitoring. In sleep mode, the DS2720 ceases monitoring activities and drives both the

charge and discharge protection FETs to an “off state”. Upon returning to the active mode from the sleep

mode, DS2720 resumes safety monitoring and conditionally turns on the protection FETs.

Table 2. POWER MODE TRANSITION CONDITIONS

Active

® Sleep

Sleep

® Active

(1)

RECHARGEABLE Li+ PROTECTION CIRCUITRY

During active mode, the DS2720 constantly monitors cell voltage and voltage drop across the FETs to

protect the battery from overcharge (overvoltage), overdischarge (undervoltage), and excessive discharge

currents (overcurrent, short circuit). Conditions and DS2720 responses are described in the sections

below and summarized in Table 3 and Figure 3.

Table 3. PROTECTION CONDITIONS AND DS2720 RESPONSES

ACTIVATION

CONDITION

NAME

THRESHOLD

DELAY

RESPONSE

RELEASE

THRESHOLD

Overvoltage

(1)

Undervoltage

(charger connected)

Recovery Charge

(while in active

(2)

Overcurrent

(3)

Short Circuit

(3)

Overtemperature