Z86L972 Datasheet, PDF (33/91 Pages) Zilog, Inc. – Low-Voltage Microcontrollers

Z86L972/Z86L973/Z86L974
Low-Voltage Microcontrollers
26
P51
(CIN1)
P50
(CREF1)
+
–
Comparator 1
IRQ2, P51 Data Latch
P456CON
Bit5 1 = comparator
0 = digital
P52
(CIN2)
P53
(CREF2)
+
–
Comparator 2
Figure 12. Analog Comparators
P456CON
Bit4 1 = comparator
0 = digital
IRQ0, P52 Data Latch
Active Glitch Filter
The Z86L972/Z86L973/Z86L974 family incorporates an active power/glitch filter
that can be used to improve the quality of the power supply when the device is
operating in noisy environments. The chips use two separate power buses:
• pad ring power bus (all the output drivers plus the crystal/RC oscillator) called
V_{DD_padring}
• core power bus (all digital circuitry) called V_DD
Depending on the pin availability, one or more of the power busses are connected
together.
The active power filter can be used in the packages that have the V_DD separate.
Figure 13 shows the internal schematic.
PS010504-1002
PRELIMINARY