Z86D99 ZILOG [Zilog, Inc.], Z86D99 Datasheet - Page 67

• Manufacturer Part Number: Z86D99
• Description: Low-Voltage Micro controllers with ADC
• Manufacturer: ZILOG [Zilog, Inc.]

PS003807-1002
Bit
Bit/Field
R/W
Reset
R = Read, W = Write, X = Indeterminate
Bit
Position
76543___
_____2__
______1_
_______0
Note: * When LVD is enabled, IRQ5 is set only for low-voltage detection. Timer 1 will not generate
an interrupt request.
Note:
Low-Battery Detect Flag (LB)
When the Z86D99/Z86L99 is used in a battery-operated application, one of the
on-chip comparators can be used to check that the V
correct operation of the device. When voltage begins to approach the V
an on-chip low-battery detection circuit is tripped, which in turn sets a user-read-
able flag. The LB register, as described in Table 18, is used to set and reset the
LB flag.
Table 18. LB Register (Group/Bank 0Dh, Register C)
The LB flag will be valid after enabling the detection for 20 S
(design estimation, not tested in production). LB does not work
at STOP mode. It must be disabled during STOP mode in order
to reduce current.
7
Reserved
W
1
Bit/Field
Reserved
Pad LVD
LVD_Flag
LVD_Enable
P
6
W
1
R
E
L
5
W
1
R/W
R
W
R
R
W
R
R
W
R/W
I
M
Z86D990/Z86D991 OTP and Z86L99X ROM
4
W
1
Value
1
X
1
0
X
1
0
X
1
0
I
Low-Voltage Microcontrollers with ADC
N
A
3
W
1
Description
Always reads 11111
No Effect
Pad is not regulated when P43=0
(V
Pad is regulating the current when
P43=0 (V
Reset Pad LB flag
LB Flag Set if
LB Flag Reset
No Effect
Enable LB *
Disable LB
R
pad
<V
Y
CC
min
2
Pad
LVD
R/W
X
pad
is at the required level for
; see page 33)
>V
V
min
DD
; see page 33)
<V
1
LVD_
Flag
R/W
0
LV
BO
0
LVD_
Enable
R/W
0
point,
60