R2051 datasheet(48/58 Pages) RICOH

Part #	R2051

Description	2 wire interface Real-Time Clock ICs with Battery Backup switch-over Function

Download	58 Pages

Scroll/Zoom	100%

Manufacturer	RICOH [RICOH electronics devices division]

Direct Link	http://www.ricoh.com

Logo

48 / 58 page

R2051 Series

48

Typical Applications

• Typical Power Circuit Configurations

VDD

VSB

VCC

VSS

0.1

µF

CPU Power

Supply

The case of back-up by

primary battery

CR2025

etc.

VSB

VDD

VCC

VSS

0.1

µF

CPU power

supply

ML614

etc.

The case of back-up by

capacitor or secondary battery

(Charging voltage is equal to CPU

power supply voltage)

VSB

VDD

VCC

VSS

0.1

µF

CPU power

supply

(3V)

5V

Double layer

capacitor

etc.

The case of back-up by

capacitor or secondary battery

(Charging voltage is not equal to

CPU power supply voltage)

VDD pin cannot be connected to any additional heavy load components such as SRAM.

And VDD pin must be

connected C2, and C2 should be over 0.1

µF.

VDD

CPU power supply

VCC

VSB

C3

VOLTAGE

DETECTOR

SW1

SW2

C2

R1

CPU

Vbat

-VDET1

Rcpu

R2051 Series

When secondary battery or double layer capacitor connects to VDD pin, after CPU power supply turning off,

secondary battery discharges through the root above figure.

If R1 is much smaller than CPU impedance (Rcpu),

VCC voltage keeps higher than -VDET1, and SW1 keeps on.

Therefore R1 must be specified by following formula.

R1 > Rcpu x (Vbat - (-VDET1)) / (-VDET1)

R1 is specified by back-up battery or double layer capacitor, too.

Please check the data sheet for back-up

devices.

Similar Part No. - R2051

Manufacturer	Part #	Datasheet	Description
RICOH electronics devic...	R2051S01-E2-F	739Kb / 49P	High precision I2C-Bus Real-Time Clock Module
RICOH electronics devic...	R2051S02-E2-F	739Kb / 49P	High precision I2 C-Bus Real-Time Clock Module

More results

Similar Description - R2051

Manufacturer	Part #	Datasheet	Description
RICOH electronics devic...	R2061K	723Kb / 56P	wire interface Real-Time Clock ICs with Battery Backup switch-over Function
	R2061L01-E2	613Kb / 60P	3 Wire Interface Real-Time Clock ICs with Battery Backup Switch-Over Function
	R2062	706Kb / 55P	3 wire interface Real-Time Clock ICs with Battery Backup switch-over Function
Intersil Corporation	ISL12008	293Kb / 19P	I2C Real Time Clock with Battery Backup
RICOH electronics devic...	R2033K	582Kb / 50P	3 wire interface Real-Time Clock ICs
	RV5C338A	440Kb / 52P	3-WIRE SERIAL INTERFACE REAL-TIME CLOCK ICs WITH VOLTAGE MONITORING FUNCTION?
	RV5C339A	421Kb / 51P	3-WIRE SERIAL INTERFACE REAL-TIME CLOCK ICs WITH VOLTAGE MONITORING FUNCTION???
	RS5C348A	452Kb / 53P	4-WIRE SERIAL INTERFACE REAL-TIME CLOCK ICs WITH VOLTAGE MONITORING FUNCTION?
	RS5C338A	578Kb / 51P	3-WIRE SERIAL INTERFACE REAL-TIME CLOCK ICs WITH VOLTAGE MONITORING FUNCTION
	RV5C387A	363Kb / 42P	I2C-bus Real-Time Clock ICs with Voltage Monitoring Function?

More results

R2051 Datasheet(PDF) 48 Page - RICOH electronics devices division

R2051 Datasheet(HTML) 48 Page - RICOH electronics devices division

Similar Part No. - R2051

Similar Description - R2051

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58

Datasheet Download

Link URL