z86d73 ZiLOG Semiconductor, z86d73 Datasheet - Page 62

• Manufacturer Part Number: z86d73
• Description: 40/44/48-pin Low-voltage
• Manufacturer: ZiLOG Semiconductor

PS019402-1103
* Preliminary value including pin parasitics
Ceramic Resonator or Crystal
C1, C2 = 47 pF TYP *
f = 8 MHz
32 kHz XTAL
C1 = 20 pF, C = 33 pF
Rd = 56 - 470K
Rf = 10 M
Clock
The Z86D73 on-chip oscillator has a high-gain, parallel-resonant amplifier, for
connection to a crystal, LC, ceramic resonator, or any suitable external clock
source (XTAL1 = Input, XTAL2 = Output). The crystal must be AT cut, 1 MHz to 8
MHz maximum, with a series resistance (RS) less than or equal to 100
Z86D73 on-chip oscillator can be driven with a low-cost RC network or other suit-
able external clock source.
For 32-kHz crystal operation, an external feedback (Rf) and a serial resistor (Rd)
are required. See Figure 32.
The crystal must be connected across XTAL1 and XTAL2 using the recommended
capacitors (capacitance greater than or equal to 22 pF) from each pin to ground.
The RC oscillator configuration is an external resistor connected from XTAL1 to
XTAL2, with a frequency-setting capacitor from XTAL1 to ground (Figure 32).
C2
Figure 32. Oscillator Configuration
C1
C1
C2
Rd
Rf
XTAL2
XTAL1
XTAL2
XTAL1
P
R
E
C2
C1
L
LC
C1, C2 = 22 pF
L = 130
f = 3 MHz *
I
External Clock
M
L
µ
H *
I
XTAL2
XTAL1
XTAL2
XTAL1
N
A
40/44/48-Pin Low-Voltage IR OTP
R
C1
Y
RC
@ 3V VCC (TYP)
C1 = 33 pF *
R = 1K *
R
XTAL2
XTAL1
Ω
. The
Z86D73
56