Datasheet

PCF2127AT All information provided in this document is subject to legal disclaimers. © NXP B.V. 2013. All rights reserved.
Product data sheet Rev. 6 — 11 July 2013 14 of 86
NXP Semiconductors
PCF2127AT
Integrated RTC, TCXO and quartz crystal
[1] Duty cycle definition: % HIGH-level time : % LOW-level time.
[2] Default value.
[3] The specified accuracy of the RTC can be only achieved with CLKOUT frequencies not equal to
32.768 kHz or if CLKOUT is disabled.
Table 11. CLKOUT frequency selection
COF[2:0] CLKOUT frequency (Hz) Typical duty cycle
[1]
000
[2][3]
32768 60 : 40 to 40 : 60
001 16384 50 : 50
010 8192 50 : 50
011 4096 50 : 50
100 2048 50 : 50
101 1024 50 : 50
110 1 50 : 50
111 CLKOUT = high-Z -