XE8807AMI026TLF Semtech, XE8807AMI026TLF Datasheet - Page 47

• Manufacturer Part Number: XE8807AMI026TLF
• Description: IC MCU LOW PWR MTP FLASH 32-TQFP
• Manufacturer: Semtech

Specifications of XE8807AMI026TLF

• Applications: Sensing Machine
• Core Processor: RISC
• Program Memory Type: FLASH (11 kB)
• Controller Series: XE8000
• Ram Size: 512 x 8
• Interface: UART, USRT
• Number Of I /o: 24
• Voltage - Supply: 2.4 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 32-TQFP, 32-VQFP
• For Use With: XE8000MP - PROG BOARD AND PROSTART2 CARD
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: XE8807AMI026TR

The oscillator characteristics are given in Table 7-11. The characteristics are valid only if the crystal and board
layout meet the specifications above.
Table 7-11. Crystal oscillator characteristics.
Note 1. This gives the relative frequency deviation from nominal for a crystal with CL=8.2pF and within the
temperature range -40°C to 85°C. The crystal tolerance, crystal aging and crystal temperature drift are not
included in this figure.
7.8
7.8.1
The user can provide an external clock instead of the internal oscillators. The external provided frequency is
internally divided by two. The external clock input pin is XIN.
The system is configured for external clock by bit EnExtClock in register RegSysClock. Using the bits in the
registers RegSysRcTrim1 and RegSysRcTrim2, the ck32kHz clock frequency can be controlled (see section
7.11).
Note: when using the external clock, the Xtal is not available.
7.8.2
The external clock has to satisfy the specifications in the table below. Correct behavior of the circuit can not be
guaranteed if the external clock signal does not respect the specifications below.
Table 7-12. External clock specifications.
Note 1. For VBAT≥2.4V
Note 2. For VBAT=VREG=1.2V
7.9
There are three possible clock sources available for the CPU clock. The RC clock is always selected after power-
up, a negative pulse on NRESET or after Sleep mode. The CPU clock selection is done with the bit CpuSel in
RegSysClock (0= fastest clock, 1= 32 kHz from Xtal if EnableXtal =1 and EnExtClock = 0 else from high
prescaler 32 kHz output).
Switching from one clock source to another is glitch free.
© Semtech 2006
Symbol
f
St_xtal
Fstab
Symbol
F
PW_1
PW_0
F
PW_1_LV
PW_0_LV
Xtal
EXT
EXT_LV
External clock
Clock source selection
External clock configuration
External clock specification
Description
Nominal frequency
Start-up time
Frequency deviation
Description
External clock
frequency
Pulse 1 width
Pulse 0 width
External clock
frequency
Pulse 1 width
Pulse 0 width
-100
0.06
0.03
TBD
TBD
Min
Min
32768
Typ
Typ
7-8
1
TBD
Max
Max
300
20
20
2
8
Unit
Hz
s
ppm
Unit
MHz
µs
µs
kHz
µs
µs
XE8806A/XE8807A
Comments
Note 1
Comments
Note 1
Note 1
Note 1
Note 2
Note 2
Note 2
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