W78E51B Winbond, W78E51B Datasheet - Page 13

• Manufacturer Part Number: W78E51B
• Description: 8-BIT MTP MICROCONTROLLER
• Manufacturer: Winbond

DC Characteristics, continued
Notes:
*1. Pins P1, P2 and P3 source a transition current when they are being externally driven from 1 to 0. The transition current reaches
*2. RST pin has an internal pull-down resistor.
*3. P0, ALE, PSEN are in the external access memory mode.
*4. XTAL1 is a CMOS input and RST is a Schmitt trigger input.
AC CHARACTERISTICS
The AC specifications are a function of the particular process used to manufacture the part, the
ratings of the I/O buffers, the capacitive load, and the internal routing capacitance. Most of the
specifications can be expressed in terms of multiple input clock periods (T
usually experience less than a 20 nS variation. The numbers below represent the performance
expected from a 0.6micron CMOS process when using 2 and 4 mA output buffers.
Input Low Voltage
(Except RST)
Input Low Voltage
RST
Input Low Voltage
XTAL1
Input High Voltage
(Except RST)
Sink Current
P1, P2, P3, P4
Input High Voltage
RST
Input High Voltage
XTAL1
Sink Current
P0, ALE, PSEN
Source Current
P1, P2, P3, P4
Source Current
P0, ALE, PSEN
its maximum value when V
(*4)
(*4)
PARAMETER
(*4)
(*4)
(*3)
(*3)
IN
is approximately 2V.
SYMBOL
V
V
V
I
I
I
I
V
V
V
SK1
SK2
SR1
SR2
IH1
IH2
IH3
IL1
IL2
IL3
V
V
V
V
V
Vs = 0.45V
V
V
V
Vs = 0.45V
V
V
V
V
TEST CONDITIONS
DD
DD
DD
DD
DD
DD
DD
DD
DD
S
DD
s
= 2.4V
= 2.4V
= 4.5V
= 4.5V
= 4.5V
= 4.5V
= 4.5V
= 4.5V
= 4.5V
= 4.5V
= 4.5V
= 4.5V
- 13 -
Preliminary W78E51B
Publication Release Date: December 1998
0.67 V
0.67 V
MIN.
-100
SPECIFICATION
2.4
-8
0
0
0
4
8
DD
DD
CP
), and actual parts will
V
V
V
DD
DD
DD
MAX.
-250
0.8
0.8
0.8
-14
12
16
+0.2
+0.2
+0.2
Revision A1
UNIT
mA
mA
mA
uA
V
V
V
V
V
V