Z86D86 Datasheet, PDF (76/80 Pages) Zilog, Inc. – 28-Pin Low-Voltage OTP Microcontroller

Z86D86
28-Pin Low-Voltage OTP Microcontroller
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Mask Selectable Options
There are six Mask Selectable Options to choose from based on ROM code
requirements. These are listed in Table 26.
Table 26. Mask Selectable Options
RC/Other
32 kHz XTAL
Port 04–07 Pull-Ups
Port 00–03 Pull-Ups
Port 20–27 Pull-Ups
Port 0:0–3 Mouse Mode 0.4 V_CC Trip
RC/XTAL
On/Off
On/Off
On/Off
On/Off
On/Off
Low Voltage/Standby
An on-chip Voltage Comparator checks that the V_CC is at the required level for
correct operation of the device. Reset is globally driven when V_CC falls below V_LV.
A further small drop in V_CC causes the XTAL1 and XTAL2 circuitry to stop the
crystal or resonator clock. Typical low-voltage power consumpion in this Low Volt-
age Standby mode (I_LV) is about 100 µA. If the V_CC is allowed to stay above Vram,
the RAM content is preserved. When the power level is returned to above V_LV, the
device performs a POR and functions normally.
Low Battery Detection and Flag
A Low Battery Detection circuit can be used to signal dropping voltage levels.
Expanded Register Bank 0Dh register 0Ch bit 0 and 1 are used for this option.
Bit D0 is used to enable/disable this function.
Bit D1 is the status flag bit of this LBD.
The minimum operating voltage varies with the temperature and operating fre-
quency, while VLV varies with temperature only.
PS008905-0105
PRELIMINARY