MC13224V_09 Datasheet, PDF (40/50 Pages) Freescale Semiconductor, Inc – Advanced ZigBee™- Compliant Platform-in-Package (PiP) for the 2.4 GHz IEEE® 802.15.4 Standard

Table 14. 32.768 Oscillator Specifications (continued)
Characteristic
Symbol
Min
Typ
Max Unit
Load capacitance
Equivalent series resistance (ESR)
11
12.5
13
pF
60
kΩ
Shunt capacitance
1.35
pF
Tolerated drive level
1
μW
1 _{Recommended crystal Abracom Corporation crystal part number ABS25-32.768-12.5-B}
2 _{Example; Stability at -20×C is: -0.034 x (25-[-20])}2_{= -68.8ppm.}
6.8 Internal Low Speed Reference Oscillator Specifications
Table 15. Internal 2 KHz Oscillator Specifications
Characteristic
Default Frequency @ 25 °C
Oscillator frequency variation over full temperature range
Calibration time (in terms of 2KHz osc clocks)
Symbol
Min
2.5
-
-
Typ
1.7
+/- 13
-
Max
3.5
-
2¹⁶-1
Unit
KHz
%
osc clks
6.9 Control Timing and CPU Bus Specifications
Table 16. MCU Control Timing
(VBATT, LREG_BK_FB = 3.3 V, T_A = 25 °C, f_ref = 24 MHz, unless otherwise noted.)
Parameter
Symbol
Min
Typical
Max
Unit
CPU Bus frequency (t_cyc = 1/f_Bus)
CPU Bus frequency with active TX or RX
f_Bus
f_ref/64 ¹
—
2
f_ref ¹
MHz
MHz
Real-time interrupt internal oscillator frequency
External reset pulse width²
2
KHz
-
4
—
osc clks
External minimum interrupt pulse width (KBI[7:4])
-
4
—
osc clks
1 _{Normal operation uses a 24 MHz reference. The MC13224V allows up to a 26 MHz max reference oscillator.}
2 _{This is the shortest pulse that is guaranteed to be recognized as a reset pin request. There always must be 3 clocks of the}
operating oscillator; this can vary from the low power oscillators to the reference oscillator.
6.9.1 Timer Module Input Characteristics
Four-bit synchronizer circuits determine the shortest input pulses that can be recognized or the fastest
clock that can be used as the optional external source to the timer counter. These synchronizers operate
from the peripheral clock rate. Table 17 shows timer input timing values.
MC13224V Technical Data, Rev. 1.2
40
Freescale Semiconductor