RTC-72421
RTC-72421 is Real time clock module(4-bit REAL TIME CLOCK MODULE) manufactured by Epson Company.
features a backup function.
Actual size
Specifications (characteristics) Absolute Max. rating
Symbol Item VDD Power source voltage VI/O Input and output voltage Storage temperature TSTG Condition Ta=+25 °C Ta=+25 °C RTC-72421 RTC-72423 RTC-72421 Soldering condition TSOL RTC-72423 Specifications -0.3 to 7.0 GND -0.3 to VDD+0.3 -55 to +85 -55 to +125
Under +260 °C within 10 s (lead part) (package should be less than +150 °C)
Terminal connection
Unit V °C
18 17 16 15 14 13 12 11 10
Twice at under +260 °C within 10 s or under +230 °C within 3 min.
Operating range
Item Operating voltage Operating temperature Data holding voltage CSI data holding time Operation restoring time Symbol VDD TOPR VDH t CDR t R Refer to the data holding timing RTC-72421 RTC-72423 Condition Specifications 4.5 to 5.5 -10 to 70 -40 to 85 2.0 to 5.5 2.0 Min. Unit V °C V µs
RTC-72423
24 23 22 21 20 19 18 17 16 15 14 13
No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
STD. P CS 0
ALE A0 A1 A2 A3 RD GND WR D3 D2 D1 D0 CS1 (VDD) (VDD) VDD
1 2 3 4 5 6 7 8 9 10 11 12 (VDD) and VDD are to have the same level of voltage. Do not connect it to any external terminals. NC is not connected internally.
No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
72423 STD. P CS 0 NC ALE A0 NC A1 NC A2 A3 RD GND WR D3 D2 D1 NC NC D0 CS1 NC (VDD) (VDD) VDD
Frequency characteristics and current consumption characteristics
Item Symbol Condition 72421 A Frequency tolerance ∆f/fo Specifications ±10 ±50 ±20 ±50 +10/-120 ±5 Max. ±10 Max. 10 Max. 5 Max. Unit
External dimensions
23.1 Max.
(Unit: mm)
Ta=+25 °C 72421 B
VDD=5 V 72423 A 72423
Aging Shock resistance Current consumption fa S.R. IDD1 IDD2
VDD=5 V, Ta=+25 °C, first year
Three drops on a hard board from 750 mm or 29400 m/s2 x 0.3 ms x 1/2 sine wave x 3 directions x 10-6/year x 10...
