PIC12LC671-04I/SM Microchip Technology, PIC12LC671-04I/SM Datasheet - Page 51

• Manufacturer Part Number: PIC12LC671-04I/SM
• Description: IC MCU OTP 1KX14 LV A/D 8-SOIJ
• Manufacturer: Microchip Technology
• Series: PIC® 12Cr

Specifications of PIC12LC671-04I/SM

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 4MHz
• Peripherals: POR, WDT
• Number Of I /o: 5
• Program Memory Size: 1.75KB (1K x 14)
• Program Memory Type: OTP
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 2.5 V ~ 5.5 V
• Data Converters: A/D 4x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-SOIC (5.3mm Width), 8-SOP, 8-SOEIAJ
• Processor Series: PIC12LC
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 128 B
• Maximum Clock Frequency: 4 MHz
• Number Of Programmable I/os: 5
• Number Of Timers: 8
• Operating Supply Voltage: 2.5 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734
• Development Tools By Supplier: ICE2000
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Connectivity: -
• Lead Free Status / Rohs Status: Details

8.5
The A/D module can operate during SLEEP mode. This
requires that the A/D clock source be set to RC
(ADCS<1:0> = 11). When the RC clock source is
selected, the A/D module waits one instruction cycle
before starting the conversion. This allows the SLEEP
instruction to be executed, which eliminates all digital
switching noise from the conversion. When the conver-
sion is completed, the GO/DONE bit will be cleared,
and the result loaded into the ADRES Register. If the
A/D interrupt is enabled, the device will wake-up from
SLEEP. If the A/D interrupt is not enabled, the A/D mod-
ule will then be turned off, although the ADON bit will
remain set.
When the A/D clock source is another clock option (not
RC), a SLEEP instruction will cause the present conver-
sion to be aborted and the A/D module to be turned off,
though the ADON bit will remain set.
Turning off the A/D places the A/D module in its lowest
current consumption state.
8.6
The overall accuracy of the A/D is less than 1 LSb for
V
all accuracy includes offset error, full scale error, and
integral error. The A/D converter is monotonic over the
full V
less when either the analog reference (V
5.0V or when the analog reference (V
V
The maximum pin leakage current is specified in the
Device Data Sheet electrical specification, parameter
#D060.
In systems where the device frequency is low, use of
the A/D RC clock is preferred. At moderate to high fre-
quencies, T
lator. T
when derived from T
phase clock transitions. This reduces, to a large extent,
the effects of digital switching noise. This is not possible
with the RC derived clock. The loss of accuracy due to
digital switching noise can be significant if many I/O
pins are active.
In systems where the device will enter SLEEP mode
after the start of the A/D conversion, the RC clock
source selection is required. In this mode, the digital
noise from the modules in SLEEP are stopped. This
method gives high accuracy.
8
DD
DD
Note:
1999 Microchip Technology Inc.
.
= 5V 10% and the analog V
s for preferred operation. This is because T
DD
AD
A/D Operation During Sleep
A/D Accuracy/Error
range. The resolution and accuracy may be
must not violate the minimum and should be
For the A/D module to operate in SLEEP,
the A/D clock source must be set to RC
(ADCS<1:0> = 11). To perform an A/D
conversion in SLEEP, the GO/DONE bit
must be set, followed by the SLEEP
instruction.
AD
should be derived from the device oscil-
OSC
, is kept away from on-chip
REF
= V
REF
DD
DD
) is less than
) is less than
. This over-
AD
,
8.7
A device reset forces all registers to their reset state.
This forces the A/D module to be turned off, and any
conversion is aborted. The value that is in the ADRES
register is not modified for a Reset. The ADRES regis-
ter will contain unknown data after a Power-on Reset.
8.8
If the input voltage exceeds the rail values (V
by greater than 0.2V, then the accuracy of the conver-
sion is out of specification.
An external RC filter is sometimes added for anti-
aliasing of the input signal. The R component should be
selected to ensure that the total source impedance is
kept under the 10 k recommended specification. Any
external components connected (via hi-impedance) to
an analog input pin (capacitor, zener diode, etc.) should
have very little leakage current at the pin.
8.9
The ideal transfer function of the A/D converter is as fol-
lows: the first transition occurs when the analog input
voltage (V
(Figure 8-3).
FIGURE 8-3:
Note:
FEh
FFh
04h
03h
02h
01h
00h
Effects of a Reset
Connection Considerations
Transfer Function
AIN
For the PIC12C67X, care must be taken
when using the GP4 pin in A/D conversions
due to its proximity to the OSC1 pin.
) is 1 LSb (or Analog V
A/D TRANSFER FUNCTION
Analog input voltage
PIC12C67X
DS30561B-page 51
REF
SS
or V
/ 256)
DD
)