RFPIC12F675H-I/SS Microchip Technology, RFPIC12F675H-I/SS Datasheet - Page 51
![IC MCU 1KX14 RF FSK/ASK 20SSOP](/photos/6/58/65895/150-20-ssop_sml.jpg)
RFPIC12F675H-I/SS
Manufacturer Part Number
RFPIC12F675H-I/SS
Description
IC MCU 1KX14 RF FSK/ASK 20SSOP
Manufacturer
Microchip Technology
Series
PIC®r
Specifications of RFPIC12F675H-I/SS
Frequency
850MHz ~ 950MHz
Applications
RKE, Security Systems
Modulation Or Protocol
ASK, FSK
Data Rate - Maximum
40 kbps
Power - Output
10dBm
Current - Transmitting
14mA
Data Interface
PCB, Surface Mount
Antenna Connector
PCB, Surface Mount
Memory Size
1024 x 14 words Flash, 128 x 8 Byte EEPROM, 64 x 8 Byte SRAM
Voltage - Supply
2V ~ 5.5V
Operating Temperature
-40°C ~ 125°C
Package / Case
20-SSOP
Processor Series
RFPIC12F
Core
PIC
Data Bus Width
8 bit
Program Memory Type
Flash
Program Memory Size
1.75 KB
Data Ram Size
64 B
Interface Type
USB
Maximum Clock Frequency
20 MHz
Number Of Programmable I/os
6
Number Of Timers
2
Maximum Operating Temperature
+ 85 C
Mounting Style
SMD/SMT
Development Tools By Supplier
ICE2000
Minimum Operating Temperature
- 40 C
On-chip Adc
4 bit
For Use With
XLT20SS-1 - SOCKET TRANSITION 18DIP 20SSOPAC124002 - MOD SKT PROMATEII 18SOIC/20SSOP
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Features
-
Lead Free Status / Rohs Status
Details
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
RFPIC12F675H-I/SS
Manufacturer:
MICROCHIP
Quantity:
12 000
Part Number:
RFPIC12F675H-I/SS
Manufacturer:
MICROCHIP/微芯
Quantity:
20 000
9.0
9.1
The transmitter is a fully integrated UHF ASK/FSK
transmitter consisting of crystal oscillator, Phase-
Locked Loop (PLL), Power Amplifier (PA) with open-
collector output, and mode control logic. There are 3
variations of this device to optimize its performance for
the most commonly used frequency bands.
TABLE 9-1:
The internal structure of the transmitter is shown in
Figure 9-1.
reference frequency set by the attached crystal. The
voltage controlled oscillator (VCO) converts the voltage
on the LF pin to a frequency. This frequency is divided
by 32 and compared to the crystal reference. If the
frequency or phase does not match the reference, the
charge pump corrects the voltage on the LF pin. The
VCO output signal is also amplified by the PA, whose
single ended output drives the user’s antenna.
The external components required are a crystal to set
the transmit frequency, a supply bypass capacitor, and
two to seven biasing/impedance matching components
to get maximum power to the antenna. The two control
signals from the microcontroller are connected exter-
nally for maximum design flexibility. The rfPIC12F675
is capable of transmitting data by Amplitude Shift
Keying (ASK) or Frequency Shift Keying (FSK).
The rfPIC12F675 is a radio frequency (RF) emitting
device. Wireless RF devices are governed by a
country’s regulating agency. For example, in the United
States it is the Federal Communications Committee
(FCC) and in Europe it is the European Conference of
Postal
(CEPT). It is the responsibility of the designer to ensure
that their end product conforms to rules and regulations
of the country of use and/or sale.
2003 Microchip Technology Inc.
RF devices require correct board level implementa-
tion in order to meet regulatory requirements. Layout
considerations are listed at the end of each subsec-
tion. It is required to place a ground plane on the PCB
to reduce unwanted radio frequency emissions.
rfPIC12F675H
rfPIC12F675K
rfPIC12F675F
Device
and
UHF ASK/FSK TRANSMITTER
Transmitter Operation
A
Telecommunications
Colpitts
FREQUENCY BANDS
290-350 MHz
390-450 MHz
850-930 MHz
Frequency
oscillator
generates
Administrations
Modulation
ASK/FSK
ASK/FSK
ASK/FSK
Preliminary
the
FIGURE 9-1:
9.2
Pins V
respectively to the transmitter. These power pins are
separate from power supply pins V
microcontroller
ground plane with the shortest possible traces. The
microcontroller ground should be tied to the same RF
ground potential. However, the V
a different potential than the microcontroller as long as
the RFEN and DATA input levels are within specifica-
tion limits.
Layout Considerations - Provide low impedance
power and ground traces to minimize spurious
emissions. A two-sided PCB with a ground plane on
the bottom layer is highly recommended. Separate
bypass capacitors should be connected as close as
possible to each of the supply pins V
Connect both V
multiple PCB vias adjacent to the V
share these PCB vias with other ground traces. Filter
the V
spurs exceed regulatory limits.
DDRF
DATA
DDRF
DATA
Supply Voltage (V
RFEN
with an RC filter if the microcontroller noise
ASK
FSK
Divide
PS
by 32
and V
.
Both V
SSRF
TRANSMITTER BLOCK
DIAGRAM
SSRF
rfPIC12F675
pins to the ground plane using
Phase/Freq
FSK Switch
Controlled
RF Power
Oscillator
Oscillator
SSRF
Amplifier
Detector
Charge
Voltage
Divider
Control
Crystal
Pump
Clock
Logic
RF
supply power and ground
pins should be tied to the
DDRF
DDRF
SSRF
DD
DS70091A-page 49
supply can be at
, V
DD
and V
REFCLK
RFXTAL
LF
ANT
V
V
V
FSK
DDRF
SSRF
SSRF
pads. Do not
SSRF
and V
OUT
SS
)
DDRF
to the
.