Datasheet

Electrical characteristics
i.MX RT1015 Crossover Processors Data Sheet for Consumer Products, Rev. 0.1, 03/2019
NXP Semiconductors 25
• Average Discharge Voltage is 2.5 V
• Maximum Charge Current is 0.6 mA
For a charge voltage of 3.2 V, Rs = (3.2-2.5)/0.6 m = 1.17 k.
4.3 I/O parameters
This section provide parameters on I/O interfaces.
4.3.1 I/O DC parameters
This section includes the DC parameters of the following I/O types:
• XTALI and RTC_XTALI (Clock Inputs) DC Parameters
• General Purpose I/O (GPIO)
NOTE
The term ‘NVCC_XXXX’ in this section refers to the associated supply rail
of an input or output.
Table 19. OSC32K main characteristics
Min Typ Max Comments
Fosc — 32.768 KHz — This frequency is nominal and determined mainly by the crystal selected.
32.0 K would work as well.
Current consumption — 4 A—The 4 A is the consumption of the oscillator alone (OSC32k). Total supply
consumption will depend on what the digital portion of the RTC consumes.
The ring oscillator consumes 1 A when ring oscillator is inactive, 20 A
when the ring oscillator is running. Another 1.5 A is drawn from vdd_rtc in
the power_detect block. So, the total current is 6.5 A on vdd_rtc when the
ring oscillator is not running.
Bias resistor — 14 M — This integrated bias resistor sets the amplifier into a high gain state. Any
leakage through the ESD network, external board leakage, or even a
scope probe that is significant relative to this value will debias the amp. The
debiasing will result in low gain, and will impact the circuit's ability to start
up and maintain oscillations.
Crystal Properties
Cload — 10 pF — Usually crystals can be purchased tuned for different Cloads. This Cload
value is typically 1/2 of the capacitances realized on the PCB on either side
of the quartz. A higher Cload will decrease oscillation margin, but
increases current oscillating through the crystal.
ESR — 50 k 100 k Equivalent series resistance of the crystal. Choosing a crystal with a higher
value will decrease the oscillating margin.