Silicon Laboratories SI4734/35-B20 - Manual (Page 16)

S i 4 7 3 4 / 3 5 - B 2 0
16 Rev. 1.0
Table 12. Reference Clock and Crystal Characteristics
(V
DD
= 2.7 to 5.5 V, V
IO
= 1.5 to 3.6 V, T
A
= –20 to 85 °C)
Parameter Symbol Test Condition Min Typ Max Unit
Reference Clock
RCLK Supported Frequencies
*
31.130 32.768 40000.0 kHz
RCLK Frequency Tolerance –50 — 50 ppm
REFCLK_PRESCALE 1 — 4095
REFCLK 31.130 32.768 34.406 kHz
Crystal Oscillator
Crystal Oscillator Frequency — 32.768 — kHz
Crystal Frequency Tolerance* –100 — 100 ppm
Board Capacitance — — 3.5 pF
*Note: The Si4734/35 divides the RCLK input by REFCLK_PRESCALE to obtain REFCLK. There are some RCLK
frequencies between 31.130 kHz and 40 MHz that are not supported. See AN332, Table 6 for more details.