ADUC824 Analog Devices, ADUC824 Datasheet - Page 38

• Manufacturer Part Number: ADUC824
• Description: Precision Analog Microcontroller: 1MIPS 8052 MCU + 8kB Flash + 16/24-Bit ADC + 12-Bit DAC
• Manufacturer: Analog Devices

Specifications of ADUC824

• Mcu Core: 8052
• Mcu Speed (mips): 1
• Sram (bytes): 256Bytes
• Gpio Pins: 34
• Adc # Channels: 4

ADuC824
Endurance quantifies the ability of the Flash/EE memory to be
cycled through many Program, Read, and Erase cycles. In real
terms, a single endurance cycle is composed of four independent,
sequential events. These events are defined as:
In reliability qualification, every byte in both the program and
data Flash/EE memory is cycled from 00 hex to FFhex until a
first fail is recorded signifying the endurance limit of the on-chip
Flash/EE memory.
As indicated in the specification pages of this data sheet, the
ADuC824 Flash/EE Memory Endurance qualification has been
carried out in accordance with JEDEC Specification A117 over
the industrial temperature range of –40°C, +25°C, and +85°C.
The results allow the specification of a minimum endurance figure
over supply and temperature of 100,000 cycles, with an endurance
figure of 700,000 cycles being typical of operation at 25°C.
Retention quantifies the ability of the Flash/EE memory to retain
its programmed data over time. Again, the ADuC824 has been
qualified in accordance with the formal JEDEC Retention Life-
time Specification (A117) at a specific junction temperature
(T
memory is cycled to its specified endurance limit described above,
before data retention is characterized. This means that the Flash/
EE memory is guaranteed to retain its data for its full specified
retention lifetime every time the Flash/EE memory is repro-
grammed. It should also be noted that retention lifetime, based
on an activation energy of 0.6 eV, will derate with T
in Figure 27.
Using the Flash/EE Program Memory
The 8 Kbyte Flash/EE Program Memory array is mapped
into the lower 8 Kbytes of the 64 Kbytes program space
addressable by the ADuC824, and is used to hold user code
in typical applications.
The program memory Flash/EE memory arrays can be pro-
grammed in one of two modes, namely:
Serial Downloading (In-Circuit Programming)
As part of its factory boot code, the ADuC824 facilitates serial
code download via the standard UART serial port. Serial down-
a. initial page erase sequence
b. read/verify sequence
c. byte program sequence
d. second read/verify sequence
J
= 55°C). As part of this qualification procedure, the Flash/EE
300
250
200
150
100
50
0
40
50
T
J
JUNCTION TEMPERATURE – C
60
ADI SPECIFICATION
100 YEARS MIN.
AT T
70
J
= 55 C
80
A single Flash/EE
Endurance Cycle
90
Memory
100
J
as shown
110
load mode is automatically entered on power-up if the external
pin, PSEN, is pulled low through an external resistor as shown
in Figure 28. Once in this mode, the user can download code to
the program memory array while the device is sited in its target
application hardware. A PC serial download executable is pro-
vided as part of the ADuC824 QuickStart development system.
The Serial Download protocol is detailed in a MicroConverter
Applications Note uC004 available from the ADI MicroConverter
Website at
Parallel Programming
The parallel programming mode is fully compatible with conven-
tional third party Flash or EEPROM device programmers. A
block diagram of the external pin configuration required to support
parallel programming is shown in Figure 29. In this mode, Ports 0,
1, and 2 operate as the external data and address bus interface,
ALE operates as the Write Enable strobe, and Port 3 is used as a
general configuration port that configures the device for various
program and erase operations during parallel programming.
The high voltage (12 V) supply required for Flash/EE program-
ming is generated using on-chip charge pumps to supply the high
voltage program lines.
SEQUENCE
PROGRAM MODE
ENTRY
(SEE TABLE XII)
COMMAND
ENABLE
www.analog.com/microconverter.
NEGATIVE
EDGE
GND
V
DD
ADuC824
5V
PSEN
V
GND
P3
P3.0
P3.6
PSEN
RESET
DD
ADuC824
1k
ALE
P0
P1
P2
PULL PSEN LOW DURING RESET
TO CONFIGURE THE ADuC824
FOR SERIAL DOWNLOAD MODE
PROGRAM
DATA
(D0–D7)
PROGRAM
ADDRESS
(A0–A13)
(P2.0 = A0)
(P1.7 = A13)
WRITE ENABLE
STROBE