PIC17LC756A-08/L Microchip Technology, PIC17LC756A-08/L Datasheet - Page 45

• Manufacturer Part Number: PIC17LC756A-08/L
• Description: IC MCU OTP 16KX16 A/D 68PLCC
• Manufacturer: Microchip Technology
• Series: PIC® 17Cr

Specifications of PIC17LC756A-08/L

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 50
• Program Memory Size: 32KB (16K x 16)
• Program Memory Type: OTP
• Ram Size: 902 x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 5.5 V
• Data Converters: A/D 12x10b
• Oscillator Type: External
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 68-PLCC
• Processor Series: PIC17LC
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 902 B
• Interface Type: I2C, MSSP, RS- 232, SCI, SPI, USART
• Maximum Clock Frequency: 8 MHz
• Number Of Programmable I/os: 50
• Number Of Timers: 8
• Operating Supply Voltage: 3 V to 5.5 V
• Maximum Operating Temperature: + 70 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: 0 C
• On-chip Adc: 12 bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

7.1.2
When either Microprocessor or Extended Microcontrol-
ler mode is selected, PORTC, PORTD and PORTE are
configured as the system bus. PORTC and PORTD are
the multiplexed address/data bus and PORTE<2:0> is
for the control signals. External components are
needed to demultiplex the address and data. This can
be done as shown in Figure 7-4. The waveforms of
address and data are shown in Figure 7-3. For com-
plete timings, please refer to the electrical specification
section.
FIGURE 7-3:
The system bus requires that there is no bus conflict
(minimal leakage), so the output value (address) will be
capacitively held at the desired value.
As the speed of the processor increases, external
EPROM memory with faster access time must be used.
Table 7-2 lists external memory speed requirements for
a given PIC17C7XX device frequency.
FIGURE 7-4:
<15:0>
2000 Microchip Technology Inc.
ALE
WR
OE
AD
Note 1: Use of I/O pins is only required for paged memory.
’1’
Q1
Address out Data in
PIC17CXXX
2: This signal is unused for ROM and EPROM devices.
3: 16-bit wide devices are now common and could be used instead of 8-bit wide devices.
EXTERNAL MEMORY INTERFACE
AD15-AD8
Q2
Read Cycle
AD7-AD0
I/O
Q3
ALE
WR
OE
(1)
EXTERNAL PROGRAM
MEMORY ACCESS
WAVEFORMS
TYPICAL EXTERNAL PROGRAM MEMORY CONNECTION DIAGRAM
Q4
Q1
Address out
Q2
Q3
Write Cycle
Data out
Q4
AD15-AD0
373
373
Q1
(3)
(3)
A15-A0
In Extended Microcontroller mode, when the device is
executing out of internal memory, the control signals
will continue to be active. That is, they indicate the
action that is occurring in the internal memory. The
external memory access is ignored.
The following selection is for use with Microchip
EPROMs. For interfacing to other manufacturers mem-
ory, please refer to the electrical specifications of the
desired PIC17C7XX device, as well as the desired
memory device to ensure compatibility.
TABLE 7-2:
The electrical specifications now include timing specifi-
cations for the memory interface with PIC17LCXXX
devices. These specifications reflect the capability of
the device by characterization. Please validate your
design with these timings.
PIC17C7XX
Frequency
Note:
Oscillator
138
16 MHz
20 MHz
25 MHz
8 MHz
(1)
The access times for this requires the use
of fast SRAMs.
D7-D0
CE
OE
Ax-A0
Memory
(MSB)
Cycle Time
Instruction
EPROM MEMORY ACCESS
TIME ORDERING SUFFIX
WR
500 ns
250 ns
200 ns
160 ns
(T
(3)
CY
(2)
)
PIC17C7XX
EPROM Suffix
DS30289B-page 45
OE
Ax-A0
D7-D0
Memory
CE
-25
-15
-10
-70
(LSB)
WR
(3)
(2)