MC68HC11EA9 Datasheet, PDF (55/58 Pages) Motorola, Inc – 8 BIT HCMOS SINGLE CHIP MICROCONTOROLLER WITH A/D CONVERTER

Freescale Semiconductor, Inc.
E CLOCK
12 E CYCLES
SAMPLE ANALOG INPUT
MSB
BIT 6 BIT 5 BIT 4 BIT 3 BIT 2 BIT 1 LSB
4
2
2
2
2
2
2
2
2
CYCLES CYC CYC CYC CYC CYC CYC CYC CYC
SUCCESSIVE APPROXIMATION SEQUENCE
END
CONVERT FIRST
CONVERT SECOND
CONVERT THIRD
CONVERT FOURTH
0
CHANNEL
AND UPDATE ADR1
32
CHANNEL
AND UPDATE ADR2
64
CHANNEL
AND UPDATE ADR3
96
CHANNEL
AND UPDATE ADR4
128 ^E
CYCLES
Figure 15 A/D Conversion Sequence
EA9 A/D CONVERSION TIM
ANALOG
INPUT
PIN
INPUT
PROTECTION
DEVICE
< 2 pF
+ ~20 V
– ~0.7 V
DIFFUSION AND
POLY COUPLER
< 4 KΩ
400 nA
JUNCTION
LEAKAGE
*
DAC
~20 pF _CAPACITANCE
VRL
*THIS ANALOG SWITCH IS CLOSED ONLY DURING THE 12-CYCLE SAMPLE TIME.
EA9 ANALOG INPUT PIN
Figure 16 Electrical Model of an A/D Input Pin (Sample Mode)
MC68HC11EA9
MC68HC11EA9TS/D
For More Information On This Product,
55
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