MCIMX31_07 Datasheet, PDF (13/108 Pages) Freescale Semiconductor, Inc – Multimedia Applications Processors

Electrical Characteristics
6 _{For normal operating conditions, PLLs’ and core supplies must maintain the following relation: PLL ≥ Core – 100 mV. In other}
words, for a 1.6 V core supply, PLL supplies must be set to 1.5 V or higher. PLL voltage must not be altered after power up,
otherwise the PLL will be unstable and lose lock. To minimize inducing noise on the PLL supply line, source the voltage from
a low-noise, dedicated supply.
7 _{Fuses might be inadvertently blown if written to while the voltage is below this minimum.}
Table 8 provides information for interface frequency limits. For more details about clocks characteristics,
see Section 4.3.8, “DPLL Electrical Specifications” on page 31 and Section 4.3.3, “Clock Amplifier
Module (CAMP) Electrical Characteristics on page 19.
Table 8. Interface Frequency
ID
Parameter
Symbol
Min
Typ
Max
Units
1 JTAG TCK Frequency
2 CKIL Frequency¹
3 CKIH Frequency²
f_JTAG
f_CKIL
f_CKIH
DC
5
10
MHz
32
32.768
38.4
kHz
15
26
75
MHz
1 _{CKIL must be driven by an external clock source to ensure proper start-up and operation of the device. CKIL is needed to}
clock the internal reset synchronizer, the watchdog, and the real-time clock.
2 _{DPTC functionality, specifically the voltage/frequency relation table, is dependent on CKIH frequency. At the time of}
publication, standard tables used by Freescale OSs provided for a CKIH frequency of 26 MHz only. Any deviation from this
frequency requires an update to the OS. For more details, refer to the particular OS user's guide documentation.
Table 9 shows the fusebox supply current parameters.
Table 9. Fusebox Supply Current Parameters
Ref. Num
Description
Symbol Minimum Typical Maximum Units
1
eFuse Program Current.¹
I_program
–
35
60
mA
Current to program one eFuse bit: efuse_pgm = 3.0V
2
eFuse Read Current²
Current to read an 8-bit eFuse word
vdd_fusebox = 1.875V
I_read
–
5
8
mA
1 _{The current Iprogram is during program time (tprogram).}
2 _{The current Iread is present for approximately 50 ns of the read access to the 8-bit word.}
i.MX31/i.MX31L Advance Information, Rev. 2.3
Freescale Semiconductor
13