User's Manual l TQMaRZG2x UM 0100 l © 2021, TQ-Systems GmbH
Page 16
3.3.3
RTC
The RTC PCF85063A (assembly option) can be supplied via V_BAT (0.9 V to 3.6 V) by a battery on the carrier board.
Signal RTC_INT is routed to the TQMaRZG2x connectors. CLKOUT is only activated if the TQMaRZG2x is supplied with 5 V.
The RTC is controlled by the I
2
C controller IIC_DVFS. The RTC has I
2
C address
The quartz used for the RTC on the TQMaRZG2x has a tolerance of ±20 ppm at +25 °C.
This results in an accuracy of approximately 2.6 seconds / day = 16 minutes / year.
RTC
(PCF85063A)
5 V
V_BAT
RZ/G2x
V_5V_IN
Coin cell
(typ. 3V)
VDD
I2C
IIC_DVFS
1.8
V ↔
3.3 V
LDO
3.3 V
RTC_INT_OUT#
3.3 V
INT#
Connector
Figure 8:
Block diagram RTC buffering
Attention: Destruction or malfunction, prohibited charging of coin cells
If the TQMaRZG2x is supplied with 5 V (V_5V_IN), V_BAT is supplied from 3.3 V generated on the
TQMaRZG2x. V_BAT can be used to charge GoldCaps
®
.
If coin cells or similar non-rechargeable sources are used, protection measures against unauthorized
charging must be provided by the carrier board.
3.3.4
Temperature sensor SE97BTP
A temperature sensor SE97BTP is provided on the TQMaRZG2x. For details about the EEPROM; see 3.3.2.6.
The open-drain Alarm Output EVENT_EVENT_TEMPSENSOR# is pulled-up to 3.3 V and routed to the TQMaRZG2x connectors.
The SE97BTP is controlled by the RZ/G2x I
2
C bus IIC_DVFS. The following table shows details of the temperature sensor.
Table 11:
Temperature sensor SE97BTP
Manufacturer
Device
Resolution
Accuracy
Temperature range
NXP
SE97BTP
11 bits
Max. ±1 °C
+75 °C to +95 °C
Max. ±2 °C
+40 °C to +125 °C
Max. ±3 °C
–40 °C to +125 °C
The temperature sensor has I
2
C address