CHAPTER 20
μ
PD78P048A
333
CHAPTER 20
μ
PD78P048A
The
μ
PD78P048A is a product integrating a one-time programmable ROM or with an on-chip EPROM
that enables program writing, erasure, and rewriting. The
μ
PD78P048A is a
μ
PD78044A Subseries device
but is also compatible with
μ
PD78044F subseries devices. Refer to Table 20-1 to check the differences
between the
μ
PD78P048A and the mask ROM versions (
μ
PD78042F, 78043F, 78044F, and 78045F).
Table 20-1. Difference between
μ
PD78P048A and Mask ROM Versions
Item
μ
PD78P048A
Mask ROM Versions
Supply voltage
V
DD
= 2.7 to 6.0 V
V
DD
= 2.7 to 5.5 V
Internal ROM configuration
One-time PROM/EPROM
Mask ROM
Internal ROM capacity
60 Kbytes
μ
PD78042F: 16 Kbytes
μ
PD78043F: 24 Kbytes
μ
PD78044F: 32 Kbytes
μ
PD78045F: 40 Kbytes
Internal high-speed RAM capacity
1024 Kbytes
μ
PD78042F: 512 Kbytes
μ
PD78043F: 512 Kbytes
μ
PD78044F: 1024 Kbytes
μ
PD78045F: 1024 Kbytes
Change in capacity of internal ROM
and high-speed RAM by means of
memory switching register (IMS)
Possible
Note1
Impossible
Internal expansion RAM size
switching register (IXS)
Available (internal expansion RAM capacity
can be changed
Note 2
by means of IXS)
This register is not provided.
IC pin
None
Available
V
PP
pin
Available
None
P80, P81, P90 to P97, P100 to P105
Pull-down resistors are not provided on
chip.
On-chip mask option pull-down
resistors are incorporated.
P30 to P37, P106, P107, P110 to
P117, P120 to P127
Pull-down resistors are not provided on
chip.
P70 to P74
Pull-up resistors are
not provided on chip.
On-chip mask option pull-up
resistors are incorporated.
Electrical specifications
Read the separate data sheet.
Notes 1.
The internal PROM capacity is set to 60 Kbytes and the internal high-speed RAM capacity is set
to 1024 bytes by RESET input.
2.
The internal expansion RAM capacity is set to 1024 bytes by RESET input.
Caution
The PROM version and mask ROM version differ in noise immunity. When replacing a PROM
version with a mask ROM version in the course of experimental production to mass
production, make a thorough evaluation with a CS version (not ES version) of the mask ROM
version.