bq4802Y

bq4802LY

SLUS464C – AUGUST 2000 – REVISED JUNE 2002

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2

Thesedevices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive foam during

storage or handling to prevent electrostatic damage to the MOS gates.

DESCRIPTION (CONTINUED)

The bq4802Y/bq4802LY provides direct connections

for a 32.768-kHz quartz crystal and a 3-V backup

battery. Through the use of the conditional chip enable

the bq4802Y/bq4802LY can write-protect and make

non- volatile external SRAMs. The backup cell powers

the real-time clock and maintains SRAM information in

the absence of system voltage. The crystal and battery

are contained within the modules for a more integrated

solution.

The bq4802Y/bq4802LY contains a temperature-

compensated reference and comparator circuit that

monitors the status of its voltage supply. When the

bq4802Y/bq4802LY

detects

an

out-of-tolerance

condition, it generates an interrupt warning and sub-

sequently a microprocessor reset. The reset stays

allow for power supply and processor stabilization. The

reset function also allows for an external push-button

override.

ORDERING INFORMATION

T

OPERATION

DEVICES

SYMBOL

TA

OPERATION

SOIC(1) (DW)

TSSOP(1) (PW)

SNAPHAT(1)(2)(3) (DSH)

SYMBOL

0

°Cto 70°C

5 V

bq4802YDW

bq4802YPW

bq4802YDSH

bq4802Y

0

°C to +70°C

3.3 V

bq4802LYDW

bq4802LYPW

bq4802LYDSH

bq4802LY

(1) The DW, PW and DSH packages are available taped and reeled. Add an R suffix to the device type (i.e., bq4802YDWR).

(2) The DSH package is available taped only.

(3) The bq48SH–28x6 should be ordered to complete the SNAPHAT module and is the same part number for both 3.3-V and 5-V modules.

CAUTION: Wave soldering of DSH package may cause damage to SNAPHAT sockets.

ABSOLUTE MAXIMUM RATINGS

over operating free-air temperature range unless otherwise noted(1)

bq4802Y

bq4802LY

Input voltage range, VCC, VT (VT ≤ VCC +0.3)

–0.3 V to 6.0 V

Operating temperature range, TJ

0

°C to 70°C

Storage temperature range, Tstg

– 55

°C to 125°C

Temperature under bias, TJbias

– 40

°C to 85°C

Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds

300

°C

(1) Stressesbeyondthoselistedunder“absolutemaximumratings”maycausepermanentdamagetothedevice.Thesearestressratingsonly,and

functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not

implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

RECOMMENDED OPERATING CONDITIONS

MIN

MAX

UNIT

Supply voltage V

bq4802Y

4.5

5.5

V

Supply voltage, VCC

bq4802LY

2.7

3.6

V

Input low voltage, VIL

–0.3

0.8

V

Input high voltage, VIH

2.2

VCC + 0.3

V

Backup cell voltage, VBC

2.4

4.0

V

Push button reset input low, VBC

–0.3

0.4

V

Push button reset input high, VPBRH

2.2

VCC + 0.3

V