Back-Up Charger Electrical Characteristics

Unless otherwise noted, V

pearing in boldface type apply over the entire junction temperature range for operation, −40˚C to +125˚C. (Notes 2, 6) and

(Note 8).

Symbol

Parameter

Conditions

Min

Typ

Max

Units

V

IN

Operational Voltage Range

Voltage at V

IN

3.3

5.5

V

I

OUT

Backup Battery Charging Current

V

Backup Battery Charger Enabled

(Note 8)

190

µA

V

OUT

Charger Termination Voltage

V

Enabled. Programmable

2.91

3.1

V

Backup Battery Charger Short

Circuit Current

Backup_Bat = 0V, Backup Battery

Charger Enabled

9mA

PSRR

Power Supply Ripple Rejection

Ratio

I

OUT

≤ 50 µA, V

V

≤ V

≤ 5.0V

15

dB

I

Q

Quiescent Current

I

25

µA

C

OUT

Output Capacitance

0 µA

≤ I

OUT

≤ 100 µA

0.1

µF

Output Capacitor ESR

5

500

M

Ω

Logic Inputs and Outputs DC Operating Conditions (Note 2)

Logic Inputs (SYS_EN, PWR_EN, SYNC, nRSTI, PWR_ON, nTEST_JIG, SPARE and GPI’s)

Symbol

Parameter

Conditions

Min

Max

Units

V

IL

Low Level Input Voltage

0.5

V

V

IH

High Level Input Voltage

V

RTC

−0.5V

V

I

LEAK

Input Leakage Current

−1

+1

µA

Logic Outputs (nRSTO, EXT_WAKEUP and GPO’s)

Symbol

Parameter

Conditions

Min

Max

Units

V

OL

Output Low Level

Load = +0.2 mA = I

0.5

V

V

OH

Output High Level

Load = −0.1 mA = I

V

RTC

−0.5V

V

I

LEAK

Output Leakage Current

V

+5

µA

Logic Output (nBATT_FLT)

Symbol

Parameter

Conditions

Min

Typ

Max

Units

nBATT_FLT Threshold Voltage

Programmable via Serial Interface

Default = 2.8V

2.4

2.8

3.4

V

V

OL

Output Low Level

Load = +0.4 mA = I

0.5

V

V

OH

Output High Level

Load = −0.2 mA = I

V

RTC

−0.5V

V

I

LEAK

Input Leakage Current

+5

µA

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