TMS370C722NT Datasheet, PDF (45/61 Pages) Texas Instruments – 8-BIT MICROCONTROLLER

XTAL2/CLKIN
XTAL1
TMS370Cx2x
8-BIT MICROCONTROLLER
SPNS018C – FEBRUARY 1993 – REVISED FEBRUARY 1997
XTAL2/CLKIN
XTAL1
C1
(see Note B)
Crystal/Ceramic
Resonator
(see Note A)
C2
(see Note B)
External
Clock Signal
C3
(see Note B)
NOTES: A. The crystal/ceramic resonator frequency is four times the reciprocal of the system clock period.
B. The values of C1 and C2 are typically 15 pF and C3 value is typically 50 pF. See the manufacturer’s recommendations for ceramic
resonators.
Figure 15. Recommended Crystal/Clock Connections
Load Voltage
1.2 kΩ
VO
20 pF
Case 1: VO = VOH = 2.4 V; Load Voltage = 0 V
Case 2: VO = VOL = 0.4 V; Load Voltage = 2.1 V
NOTE A: All measurements are made with the pin loading as shown unless otherwise noted. All measurements are made with XTAL2/CLKIN
driven by an external square wave signal with a 50% duty cycle and rise and fall times less than 10 ns unless otherwise stated.
Figure 16. Typical Output Load Circuit (See Note A)
VCC
VCC
300 Ω
30 Ω
I/O
20 Ω
Pin Data
Output
Enable
6 kΩ
INT1
20 Ω
GND
GND
Figure 17. Typical Buffer Circuitry
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