View FX809_247335.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

FX809 FFSK Modem
Recovered Clock
CHECKSUM GEN/CHECK
VDD
BYTE COUNTER
Rx IN
FFSK RECEIVER
Recovered Clock
DATA REGISTER 1
DATA REGISTER 2
FFSK TRANSMITTER
TX OUT
XTAL/CLOCK CLOCK XTAL GENERATOR
Rx SYNC Detect
SYNC/SYNC DETECT
Rx SYNC Detect
VBIAS
Rx FREE FORMAT CS
RX DATA BUFFER
TX DATA BUFFER AMP IN
REPLY DATA
Rx Data Ready Interrupt Enable
Tx Data Ready
Tx Idle
SYNC PROGRAM LOW - HIGH
- + AMP OUT
SERIAL CLOCK
C-BUS INTERFACE AND CONTROL LOGIC
8-Bit Parallel Bus
UNCOMMITTED VBIAS
Rx SYNC Detect Rx SYNC Detect
AMPLIFIER V SS
COMMAND DATA
ADDRESS DECODER
CONTROL REGISTER
STATUS REGISTER
INTERRUPT GENERATOR
IRQ
WAKE
ADDRESS SELECT
Fig 1. FX809 FFSK Modem
Brief Description
An intelligent, half-duplex, FFSK/MSK modem which operates under "C-BUS" control. In addition this modem provides software selectable checksum generation and error checking, in accordance with MPT1327. The FX809, using Interrupt and Status Register procedures, performs the functions described below: In Tx mode the FX809 will: 1. (a) Accept from the host and transmit, 8-bit bytes of data as instructed (Preamble, Sync, Address and data). (b) internally calculate and insert a 2 byte checksum based upon the preceeding 6 bytes of data, or (c) disable the internal checksum generator and continuously transmit the data supplied. 2. Transmit 1 hang-bit and go to Tx Idle when all loaded data bytes have been transmitted. In Rx mode the FX809 will: 1. Detect and achieve bit synchronization within 16 bits. 2. (a) Search and detect the user-programmed Sync (or its opposite logic sense) Word and achieve frame sychronization. Data will then be output in 8-bit bytes via the Rx Data Buffer. Publication D/809/5 April 1998 (b) Use the received checksum to calculate the presence of any errors, setting the Status Register accordingly. 3. Make the incoming data directly available, via the Rx Data Buffer (Rx Freeformat), overriding synchronization requirements. The FX809 achieves Rx input timing by recovering an Rx clock from the incoming data stream. Output tones are timed to the internally generated transmit clock. Filter, register clocks and transmit FFSK tone frequencies are derived internally from the external Xtal or clock pulse input. For compliance with the MPT 1327 Signalling Specification a 4.032MHz Xtal or clock input will be required.
NOTE: All information contained in this data sheet is specified using a 4.032 MHz Xtal, 1200 bps baud rate , Mark and Space frequencies 1200 Hz and 1800 Hz.
The FX809 is a low-power 5-volt integrated circuit, incorporating "Powersave" modes to further reduce power requirements. An uncommitted amplifier is provided on chip for general purpose applications within DBS 800. The FX809 is available in 24-pin cerdip DIL and 24pin/lead plastic SMD packages.
Pin Number Function
FX809 J/LG/LS 1 Xtal: The output of the on-chip clock oscillator. External components are required at this input when a Xtal input is used. See Figure 2, INSET.
2
Xtal/Clock: The input to the on-chip clock oscillator inverter. A Xtal or externally derived clock should be connected here. See Figure 2, INSET.
3
Interrupt Request (IRQ): The output of this pin indicates an interrupt condition to the Controller, by going to a logic "0." This is a "wire-or able" output, enabling the connection of up to 8 peripherals to 1 interrupt port on the Controller. This pin has a low-impedance pulldown to logic "0" when active and a high-impedance when inactive. The system IRQ line requires a 'pull-up' resistor to VDD. The conditions that cause interrupts are indicated in the Status Register and are shown below: Tx Idle Rx Data Ready Tx Data Ready Rx SYNC Detect Rx SYNC Detect Interrupt outputs can be disabled by bit 3 of the Control Register.
No Internal connection. 4 No Internal connection. 5 Rx Freeformat: Used in the Rx mode, this input, when a logic "0," allows received data to be read from the Rx Data Buffer via the Reply Data line without having to acheive byte synchronization (SYNC/SYNC) first. Data will continue to be available after this input goes to a logic "1" until either a SYNC or SYNC Prime bit is set or the the modem set to Tx mode. When held at a logic "1" the modem operates normally. This pin has an internal 1M pullup resistor. NOTE: If this input is held at a logic "0" in the Tx mode, the Rx Data Ready bit in the Status Register may occasionally be set, but not cause an interrupt. If this input is a logic "0" when going into the Rx mode, an Rx Data Ready interrupt may be generated immediately, in this case the first byte of Rx data should be ignored.
6
7
VBIAS : The internal circuitry bias line, held at VDD/2 this pin must be decoupled to VSS by capacitor C3, see Figure 2. Amp In: The inverting input to the on-chip uncommitted amplifier .
8 Amp Out: The output of the on-chip uncommitted amplifier. 9 Rx In: The 1200 baud, 1200Hz/1800Hz, received FFSK signal input. The input signal to this pin must be a.c. coupled via capacitor C4, see Figure 2. No Internal connection. 11 VSS: Negative Supply (GND).
10
12
External Components
VDD C5
R4
SEE INSET XTAL XTAL/CLOCK IRQ
1 2 3 4 5
24 23 22 21 20
VDD WAKE ADDRESS SELECT SERIAL CLOCK COMMAND DATA CS
Rx FREEFORMAT VBIAS SIGNAL IN C7 SIGNAL OUT Rx IN C4 VSS R2 C6 R3
6 7 8 9 10 11 12
FX809J
19 18 17 16 15 14 13
Tx OUT REPLY DATA
C3
VSS
INSET
XTAL
Component
1
Value
X1
R1
FX809J
XTAL/CLOCK C2 C1 V
SS
2
Fig.2 External Components
R1 = 1.0M Note 1: R2 Note 1 R2, R3 and C7 form the gain R3 100k components for the signal; R4 22.0k R3 should be chosen as C1 33.0pF required by the signal input 33.0pF C2 level. C3 1.0F C4 0.1F C5 1.0F C6 33.0pF Note 1 C7 X1 4.032MHz Tolerance: R = 10% C = 20%
Modem Performance
2 x 10 -2 10 -2
Bit Error Rate (Logarithmic Scale)
Ideal Coherent FFSK Characteristic
10 -3
FX809 Characteristic
10 -4 8 6 4 3 2 10
-5
(Linear Scale )
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Signal to Noise Ratio (dB) [Bit-Rate Bandwidth]
Fig.3 Bit Error Rate vs Signal-to-Noise Ratio
Package Outlines
The FX809 is available in the package styles outlined below. Mechanical package diagrams and specifications are detailed in Section 10 of this document. Pin 1 identification marking is shown on the relevant diagram and pins on all package styles number anti-clockwise when viewed from the top.
Handling Precautions
The FX809 is a CMOS LSI circuit which includes input protection. However precautions should be taken to prevent static discharges which may cause damage.
FX809J
24-pin cerdip DIL
(J4)
FX809LG
24-pin quad plastic encapsulated bent and cropped (L1)
NOT TO SCALE
NOT TO SCALE
Max. Body Length Max. Body Width
32.03mm 14.81mm
Max. Body Length Max. Body Width
10.25mm 10.25mm
FX809LS
24-lead plastic leaded chip carrier (L2)
NOT TO SCALE
Ordering Information
FX809J FX809LG FX809LS 24-pin cerdip DIL (J4)
24-pin encapsulated bent and cropped (L1) 24-lead plastic leaded chip carrier (L2)
Max. Body Length Max. Body Width 10.40mm 10.40mm
CML does not assume any responsibility for the use of any circuitry described. No circuit patent licences are implied and CML reserves the right at any time without notice to change the said circuitry.
CML Microcircuits
COMMUNICATION SEMICONDUCTORS
CML Product Data
In the process of creating a more global image, the three standard product semiconductor companies of CML Microsystems Plc (Consumer Microcircuits Limited (UK), MX-COM, Inc (USA) and CML Microcircuits (Singapore) Pte Ltd) have undergone name changes and, whilst maintaining their separate new names (CML Microcircuits (UK) Ltd, CML Microcircuits (USA) Inc and CML Microcircuits (Singapore) Pte Ltd), now operate under the single title CML Microcircuits. These companies are all 100% owned operating companies of the CML Microsystems Plc Group and these changes are purely changes of name and do not change any underlying legal entities and hence will have no effect on any agreements or contacts currently in force. CML Microcircuits Product Prefix Codes Until the latter part of 1996, the differentiator between products manufactured and sold from MXCOM, Inc. and Consumer Microcircuits Limited were denoted by the prefixes MX and FX respectively. These products use the same silicon etc. and today still carry the same prefixes. In the latter part of 1996, both companies adopted the common prefix: CMX. This notification is relevant product information to which it is attached.
Company contact information is as below:
CML Microcircuits (UK)Ltd
COMMUNICATION SEMICONDUCTORS
CML Microcircuits (USA) Inc.
COMMUNICATION SEMICONDUCTORS
CML Microcircuits (Singapore)PteLtd
COMMUNICATION SEMICONDUCTORS
Oval Park, Langford, Maldon, Essex, CM9 6WG, England Tel: +44 (0)1621 875500 Fax: +44 (0)1621 875600 uk.sales@cmlmicro.com www.cmlmicro.com
4800 Bethania Station Road, Winston-Salem, NC 27105, USA Tel: +1 336 744 5050, 0800 638 5577 Fax: +1 336 744 5054 us.sales@cmlmicro.com www.cmlmicro.com
No 2 Kallang Pudding Road, 09-05/ 06 Mactech Industrial Building, Singapore 349307 Tel: +65 7450426 Fax: +65 7452917 sg.sales@cmlmicro.com www.cmlmicro.com
D/CML (D)/1 February 2002

▲Up To Search▲

Price & Availability of FX809

	To Download FX809 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .