Features
• Two Different IF Receiving Bandwidth Versions Are Available
(BIF = 300 kHz or 600 kHz)
• Frequency Receiving Range of
f0 = 868 MHz to 870 MHz or f0 = 902 MHz to 928 MHz
• 30 dB Image Rejection • Receiving Bandwidth BIF = 600 kHz for Low Cost 90-ppm Crystals and BIF = 300 kHz for • • • • • • • • • • • •
55 ppm Crystals Fully Integrated LC-VCO and PLL Loop Filter Very High Sensitivity with Power Matched LNA High System IIP3 (–16 dBm), System 1-dB Compression Point (–25 dBm) High Large-signal Capability at GSM Band (Blocking –30 dBm at +20 MHz, IIP3 = –12 dBm at +20 MHz) 5V to 20V Automotive Compatible Data Interface Data Clock Available for Manchester- and Bi-phase-coded Signals Programmable Digital Noise Suppression Low Power Consumption Due to Configurable Polling Temperature Range –40°C to +105°C ESD Protection 2 kV HBM, All Pins Communication to Microcontroller Possible Via a Single Bi-directional Data Line Low-cost Solution Due to High Integration Level with Minimum External Circuitry Requirements
UHF ASK/FSK Receiver ATA5760 ATA5761
1. Description
The ATA5760/ATA5761 is a multi-chip PLL receiver device supplied in an SO20 package. It has been especially developed for the demands of RF low-cost data transmission systems with data rates from 1 kBaud to 10 kBaud in Manchester or Bi-phase code. The receiver is well suited to operate with the Atmel’s PLL RF transmitter T5750. Its main applications are in the areas of telemetering, security technology and keyless-entry systems. It can be used in the frequency receiving range of f0 = 868 MHz to 870 MHz or f0 = 902 MHz to 928 MHz for ASK or FSK data transmission. All the statements made below refer to 868.3 MHz and 915.0 MHz applications. Figure 1-1. System Block Diagram
UHF ASK/FSK Remote control receiver
UHF ASK/FSK Remote control transmitter
T5750
ATA5760/ ATA5761 Demod.
PLL
IF Amp
Control
1...5
µC
XTO
Antenna VCO
Antenna PLL XTO
Power amp.
LNA
VCO
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Figure 1-2.
Block Diagram
CDEM
FSK/ASKdemodulator and data filter Rssi Limiter out RSSI IF
Dem_out
Data interface
DATA
SENS AVCC AGND DGND DVCC
POLLING/_ON
Sensitivityreduction Polling circuit and control logic
Amp.
DATA_CLK
4. Order f0 = 950 kHz/ 1 MHz
FE
CLK
IC_ACTIVE
LPF fg = 2.2 MHz Standby logic
IF Amp.
Loopfilter
Poly-LPF fg = 7 MHz LC-VCO XTO
XTAL
LNAREF
f f :2 :256
LNA_IN LNAGND
LNA
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2. Pin Configuration
Figure 2-1. Pinning SO20
SENS 1 20 DATA
IC_ACTIVE
2
19
CDEM
3
18
DGND
AVCC
4
17
DATA_CLK
TEST 1
5
16
TEST 4
AGND
6
ATA5760/ ATA5761
15
DVCC
NC
7
14
XTAL
LNAREF
8
13
NC
LNA_IN
9
12
TEST 3
LNAGND 10
11
TEST 2
Table 2-1.
Pin 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Pin Description
Symbol SENS IC_ACTIVE CDEM AVCC TEST 1 AGND NC LNAREF LNA_IN LNAGND TEST 2 TEST 3 NC XTAL DVCC TEST 4 DATA_CLK DGND POLLING/_ON DATA Function Sensitivity-control resistor IC condition indicator: Low = sleep mode, High = active mode Lower cut-off frequency data filter Analog power supply Test pin, during operation at GND Analog ground Not connected, connect to GND High-frequency reference node LNA and mixer RF input DC ground LNA and mixer Do not connect during operating Test pin, during operation at GND Not connected, connect to GND Crystal oscillator XTAL connection Digital power supply Test pin, during operation at DVCC Bit clock of data stream Digital ground Selects polling or receiving mode; Low: receiving mode, High: polling mode Data output/configuration input
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3. RF Front End
The RF front end of the receiver is a low-IF heterodyne configuration that converts the input signal into an about 1 MHz IF signal with an image rejection of typical 30 dB. According to Figure 2-1 on page 3 the front end consists of an LNA (Low Noise Amplifier), LO (Local Oscillator), I/Q mixer, polyphase lowpass filter and an IF amplifier. The PLL generates the carrier frequency for the mixer via a full integrated synthesizer with integrated low noise LC-VCO (Voltage Controlled Oscillator) and PLL-loop filter. The XTO (crystal oscillator) generates the reference frequency fXTO. The integrated LC-VCO generates two times the mixer drive frequency fVCO. The I/Q signals for the mixer are generated with a divide by two circuit (fLO = fVCO/2). fVCO is divided by a factor of 256 and feeds into a phase frequency detector and compared with fXTO. The output of the phase frequency detector is fed into an integrated loop filter and thereby generates the control voltage for the VCO. If fLO is determined, fXTO can be calculated using the following formula: fXTO = fLO/128 The XTO is a one-pin oscillator that operates at the series resonance of the quartz crystal with high current but low voltage signal, so that there is only a small voltage at the crystal oscillator frequency at pin XTAL. According to Figure 3-1, the crystal should be connected to GND with a series capacitor CL. The value of that capacitor is recommended by the crystal supplier. Due to a somewhat inductive impedance at steady state oscillation and some PCB parasitics a lower value of CL is normally necessary. The value of CL should be optimized for the individual board layout to achieve the exact value of fXTO (the best way is to use a crystal with known load resonance frequency to find the right value for this capacitor) and hereby of fLO. When designing the system in terms of receiving bandwidth and local oscillator accuracy, the accuracy of the crystal and the XTO must be considered. If a crystal with ±30 ppm adjustment tolerance at 25°C, ±50 ppm over temperature –40°C to +105°C, ±10 ppm of total aging and a CM (motional capacitance) of 7 fF is used, an additional XTO pulling of ±30 ppm has to be added. The resulting total LO tolerance of ±120 ppm agrees with the receiving bandwidth specification of the 600 kHz version of ATA5760/ATA5761 if the T5750 has also a total LO tolerance of ±120 ppm. For the ATA5760N3 crystals with ±55 ppm total tolerance are needed for receiver and transmitter to cope with the reduced IF-bandwidth. Figure 3-1. XTO Peripherals
VS DVCC CL XTAL NC TEST 3 TEST 2
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The nominal frequency fLO is determined by the RF input frequency fRF and the IF frequency fIF using the following formula (low side injection): fLO = fRF - fIF To determine fLO, the construction of the IF filter must be considered at this point. The nominal IF frequency is fIF = 950 kHz. To achieve a good accuracy of the filter corner frequencies, the filter is tuned by the crystal frequency fXTO. This means that there is a fixed relation between fIF and fLO. fIF = fLO/915 for BIF = 600 kHz fIF = fLO/878 for BIF = 300 kHz The relation is designed to achieve the nominal IF frequency of fIF = 950 kHz for the 868.3 MHz and BIF = 600 kHz version, fIF = 989 kHz for the 868.3 MHz and BIF = 300 kHz version and for the 915 MHz version an IF frequency of fIF = 1.0 MHz results. The RF input either from an antenna or from an RF generator must be transformed to the RF input pin LNA_IN. The input impedance of that pin is provided in the electrical parameters. The parasitic board inductances and capacitances influence the input matching. The RF receiver ATA5760/ATA5761 exhibits its highest sensitivity if the LNA is power matched. This makes the matching to an SAW filter as well as to 50Ω or an antenna easier. Figure 14-1 on page 30 shows a typical input matching network for fRF = 868.3 MHz to 50Ω. Figure 14-2 on page 30 illustrates an according input matching for 868.3 MHz to an SAW. The input matching network shown in Figure 14-1 on page 30 is the reference network for the parameters given in the electrical characteristics.
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4. Analog Signal Processing
4.1 IF Filter
The signals coming from the RF front-end are filtered by the fully integrated 4th-order IF filter. The IF center frequency is fIF = 950 kHz for the 868.3 MHz and BIF = 600 kHz version, fIF = 989 kHz for the 868.3 MHz and BIF = 300 kHz version and fIF = 1 MHz for the 915 MHz version. The nominal bandwidth is B IF = 600 kHz for ATA5760/ATA5761 and B IF = 300 kHz for ATA5760N3.
4.2
Limiting RSSI Amplifier
The subsequent RSSI amplifier enhances the output signal of the IF amplifier before it is fed into the demodulator. The dynamic range of this amplifier is ΔRRSSI = 60 dB. If the RSSI amplifier is operated within its linear range, the best S/N ratio is maintained in ASK mode. If the dynamic range is exceeded by the transmitter signal, the S/N ratio is defined by the ratio of the maximum RSSI output voltage and the RSSI output voltage due to a disturber. The dynamic range of the RSSI amplifier is exceeded if the RF input signal is about 60 dB higher compared to the RF input signal at full sensitivity. In FSK mode the S/N ratio is not affected by the dynamic range of the RSSI amplifier, because only the hard limited signal from a high gain limiting amplifier is used by the demodulator. The output voltage of the RSSI amplifier is internally compared to a threshold voltage VTh_red. VTh_red is determined by the value of the external resistor RSens. RSens is connected between pin SENS and GND or VS. The output of the comparator is fed into the digital control logic. By this means it is possible to operate the receiver at a lower sensitivity. If RSens is connected to GND, the receiver switches to full sensitivity. It is also possible to connect the pin SENS directly to GND to get the maximum sensitivity. If RSens is connected to VS, the receiver operates at a lower sensitivity. The reduced sensitivity is defined by the value of RSens, the maximum sensitivity by the signal-to-noise ratio of the LNA input. The reduced sensitivity depends on the signal strength at the output of the RSSI amplifier. Since different RF input networks may exhibit slightly different values for the LNA gain, the sensitivity values given in the electrical characteristics refer to a specific input matching. This matching is illustrated in Figure 14-1 on page 30 and exhibits the best possible sensitivity and at the same time power matching at RF_IN. RSens can be connected to VS or GND via a microcontroller. The receiver can be switched from full sensitivity to reduced sensitivity or vice versa at any time. In polling mode, the receiver will not wake up if the RF input signal does not exceed the selected sensitivity. If the receiver is already active, the data stream at pin DATA will disappear when the input signal is lower than defined by the reduced sensitivity. Instead of the data stream, the pattern according to Figure 4-1 is issued at pin DATA to indicate that the receiver is still active (see Figure 13-2 on page 28). Figure 4-1. Steady L State Limited DATA Output Pattern
DATA tDATA_min tDATA_L_max
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4.3 FSK/ASK Demodulator and Data Filter
The signal coming from the RSSI amplifier is converted into the raw data signal by the ASK/FSK demodulator. The operating mode of the demodulator is set via the bit ASK/_FSK in the OPMODE register. Logic L sets the demodulator to FSK, applying H to ASK mode. In ASK mode an automatic threshold control circuit (ATC) is employed to set the detection reference voltage to a value where a good signal to noise ratio is achieved. This circuit also implies the effective suppression of any kind of in-band noise signals or competing transmitters. If the S/N (ratio to suppress in-band noise signals) exceeds about 10 dB the data signal can be detected properly, but better values are found for many modulation schemes of the competing transmitter. The FSK demodulator is intended to be used for an FSK deviation of 10 kHz ≤Δf ≤100 kHz. In FSK mode the data signal can be detected if the S/N (ratio to suppress in-band noise signals) exceeds about 2 dB. This value is valid for all modulation schemes of a disturber signal. The output signal of the demodulator is filtered by the data filter before it is fed into the digital signal processing circuit. The data filter improves the S/N ratio as its passband can be adopted to the characteristics of the data signal. The data filter consists of a 1st-order high pass and a 2nd-order lowpass filter. The highpass filter cut-off frequency is defined by an external capacitor connected to pin CDEM. The cut-off frequency of the highpass filter is defined by the following formula: 1 fcu_DF = -----------------------------------------------------------2 × π × 30 k Ω × CDEM In self-polling mode, the data filter must settle very rapidly to achieve a low current consumption. Therefore, CDEM cannot be increased to very high values if self-polling is used. On the other hand CDEM must be large enough to meet the data filter requirements according to the data signal. Recommended values for CDEM are given in the electrical characteristics. The cut-off frequency of the lowpass filter is defined by the selected baud-rate range (BR_Range). The BR_Range is defined in the OPMODE register (refer to section “Configuration of the Receiver” on page 23). The BR_Range must be set in accordance to the used baud-rate. The ATA5760/ATA5761 is designed to operate with data coding where the DC level of the data signal is 50%. This is valid for Manchester and Bi-phase coding. If other modulation schemes are used, the DC level should always remain within the range of V DC_m in = 33% and VDC_max = 66%. The sensitivity may be reduced by up to 2 dB in that condition. Each BR_Range is also defined by a minimum and a maximum edge-to-edge time (tee_sig). These limits are defined in the electrical characteristics. They should not be exceeded to maintain full sensitivity of the receiver.
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5. Receiving Characteristics
The RF receiver ATA5760/ATA5761 can be operated with and without a SAW front-end filter. In a typical automotive application, a SAW filter is used to achieve better selectivity and large signal capability. The receiving frequency response without a SAW front-end filter is illustrated in Figure 5-1 and Figure 5-2 on page 8. This example relates to ASK mode and the 600 kHz version ATA5760N3. FSK mode exhibits a similar behavior. The plots are printed relatively to the maximum sensitivity. If a SAW filter is used, an insertion loss of about 3 dB must be considered, but the overall selectivity is much better. When designing the system in terms of receiving bandwidth, the LO deviation must be considered as it also determines the IF center frequency. The total LO deviation is calculated, to be the sum of the deviation of the crystal and the XTO deviation of the ATA5760/ATA5761. Low-cost crystals are specified to be within ±90 ppm over tolerance, temperature and aging. The XTO deviation of the ATA5760/ATA5761 is an additional deviation due to the XTO circuit. This deviation is specified to be ±30 ppm worst case for a crystal with CM = 7 fF. If a crystal of ±90 ppm is used, the total deviation is ±120 ppm in that case. Note that the receiving bandwidth and the IF-filter bandwidth are equivalent in ASK mode but not in FSK mode. Figure 5-1. Narrow Band Receiving Frequency Response (BIF = 600 kHz)
0.0
-10.0
-20.0
dP (dB)
-30.0
-40.0
-50.0
-60.0 -4.0 -3.0 -2.0 -1.0 0.0 1.0 2.0 3.0 4.0
df (MHz)
Figure 5-2.
Wide Band Receiving Frequency Response (BIF = 600 kHz)
0.0 -10.0 -20.0 -30.0 -40.0
dP (dB)
-50.0 -60.0 -70.0 -80.0 -90.0 -100.0 -12.0
-9.0
-6.0
-3.0
0.0
3.0
6.0
9.0
12.0
df (MHz)
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6. Polling Circuit and Control Logic
The receiver is designed to consume less than 1 mA while being sensitive to signals from a corresponding transmitter. This is achieved via the polling circuit. This circuit enables the signal path periodically for a short time. During this time the bit-check logic verifies the presence of a valid transmitter signal. Only if a valid signal is detected, the receiver remains active and transfers the data to the connected microcontroller. If there is no valid signal present, the receiver is in sleep mode most of the time resulting in low current consumption. This condition is called polling mode. A connected microcontroller is disabled during that time. All relevant parameters of the polling logic can be configured by the connected microcontroller. This flexibility enables the user to meet the specifications in terms of current consumption, system response time, data rate etc. Regarding the number of connection wires to the microcontroller, the receiver is very flexible. It can be either operated by a single bi-directional line to save ports to the connected microcontroller or it can be operated by up to five uni-directional ports.
7. Basic Clock Cycle of the Digital Circuitry
The complete timing of the digital circuitry and the analog filtering is derived from one clock. This clock cycle TClk is derived from the crystal oscillator (XTO) in combination with a divide by 14 circuit. According to section “RF Front End” on page 4, the frequency of the crystal oscillator (fXTO) is defined by the RF input signal (fRFin) which also defines the operating frequency of the local oscillator (fLO). The basic clock cycle is TClk = 14/fXTO giving TClk = 2.066 µs for fRF = 868.3 MHz and TClk = 1.961 µs for fRF = 915 MHz. TClk controls the following application-relevant parameters: • Timing of the polling circuit including bit check • Timing of the analog and digital signal processing • Timing of the register programming • Frequency of the reset marker • IF filter center frequency (fIF0) Most applications are dominated by two transmission frequencies: fTransmit = 915 MHz is mainly used in USA, fTransmit = 868.3 MHz in Europe. In order to ease the usage of all TClk-dependent parameters on this electrical characteristics display three conditions for each parameter. • Application USA (fXTO = 7.14063 MHz, TClk = 1.961 µs) • Application Europe (fXTO = 6.77617 MHz, TClk = 2.066 µs) for BIF = 600 kHz (fXTO = 6.77587 MHz, TClk = 2.066 µs) for BIF = 300 kHz • Other applications The electrical characteristic is given as a function of TClk. The clock cycle of some function blocks depends on the selected baud-rate range (BR_Range) which is defined in the OPMODE register. This clock cycle TXClk is defined by the following formulas for further reference: BR_Range = BR_Range0: BR_Range1: BR_Range2: BR_Range3: TXClk = 8 × TXClk = 4 × TXClk = 2 × TXClk = 1 × TClk TClk TClk TClk
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8. Polling Mode
According to Figure 8-4 on page 13, the receiver stays in polling mode in a continuous cycle of three different modes. In sleep mode the signal processing circuitry is disabled for the time period TSleep while consuming low current of IS = ISoff. During the start-up period, TStartup, all signal processing circuits are enabled and settled. In the following bit-check mode, the incoming data stream is analyzed bit by bit contra a valid transmitter signal. If no valid signal is present, the receiver is set back to sleep mode after the period TBit-check. This period varies check by check as it is a statistical process. An average value for TBit-check is given in the electrical characteristics. During TStartup and TBit-check the current consumption is IS = ISon. The condition of the receiver is indicated on pin IC_ACTIVE. The average current consumption in polling mode is dependent on the duty cycle of the active mode and can be calculated as: I Soff × T Sleep + I Son × ( T Startup + T Bit-check ) = --------------------------------------------------------------------------------------------------------------T Sleep + T Startup + T Bit-check
Spoll
During TSleep and TStartup the receiver is not sensitive to a transmitter signal. To guarantee the reception of a transmitted command the transmitter must start the telegram with an adequate preburst. The required length of the preburst depends on the polling parameters TSleep, TStartup, TBit-check and the start-up time of a connected microcontroller (TStart_microcontroller). Thus, TBit-check depends on the actual bit rate and the number of bits (NBit-check) to be tested. The following formula indicates how to calculate the preburst length. TPreburst ≥ TSleep + TStartup + TBit-check + TStart_microcontroller
8.1
Sleep Mode
The length of period TSleep is defined by the 5-bit word Sleep of the OPMODE register, the extension factor XSleep (according to Table 11-8 on page 25), and the basic clock cycle T Clk. It is calculated to be: TSleep = Sleep × XSleep × 1024 × TClk In US- and European applications, the maximum value of TSleep is about 60 ms if XSleep is set to 1. The time resolution is about 2 ms in that case. The sleep time can be extended to almost half a second by setting XSleep to 8. XSleep can be set to 8 by bit XSleepStd to’1’. According to Table 11-7 on page 25, the highest register value of sleep sets the receiver into a permanent sleep condition. The receiver remains in that condition until another value for Sleep is programmed into the OPMODE register. This function is desirable where several devices share a single data line and may also be used for microcontroller polling – via pin POLLING/_ON, the receiver can be switched on and off.
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Figure 8-1. Polling Mode Flow Chart
Sleep mode: All circuits for signal processing are disabled. Only XTO and Polling logic is enabled. Output level on Pin IC_ACTIVE => low IS = ISoff TSleep = Sleep x XSleep x 1024 x TClk
Sleep: XSleep: TClk:
Start-up mode: The signal processing circuits are enabled. After the start-up time (TStartup) all circuits are in stable condition and ready to receive. Output level on Pin IC_ACTIVE => high IS = ISon TStartup
5-bit word defined by Sleep0 to Sleep4 in OPMODE register Extension factor defined by XSleepStd according to Table 9 Basic clock cycle defined by fXTO and Pin MODE Is defined by the selected baud rate range and TClk. The baud-rate range is defined by Baud0 and Baud1 in the OPMODE register.
TStartup:
Bit-check mode: The incoming data stream is analyzed. If the timing indicates a valid transmitter signal, the receiver is set to receiving mode. Otherwise it is set to Sleep mode. Output level on Pin IC_ACTIVE => high IS = ISon TBit-check NO Bit check OK ?
T Bit-check :
Depends on the result of the bit check If the bit check is ok, TBit-check depends on the number of bits to be checked (NBit-check) and on the utilized data rate. If the bit check fails, the average time period for that check depends on the selected baud-rate range and . on T Clk The baud-rate range is defined by Baud0 and Baud1 in the OPMODE register.
YES Receiving mode: The receiver is turned on permanently and passes the data stream to the connected microcontroller. It can be set to Sleep mode through an OFF command via Pin DATA or POLLING/_ON. Output level on Pin IC_ACTIVE => high IS = ISon OFF command
Figure 8-2.
Timing Diagram for Complete Successful Bit Check
Bit check ok
(Number of checked Bits: 3)
IC_ACTIVE Bit check 1/2 Bit Dem_out Data_out (DATA) 1/2 Bit 1/2 Bit 1/2 Bit 1/2 Bit 1/2 Bit
TStart-up Start-up mode
T Bit-check Bit-check mode Receiving mode
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8.2
Bit-check Mode
In bit-check mode the incoming data stream is examined to distinguish between a valid signal from a corresponding transmitter and signals due to noise. This is done by subsequent time frame checks where the distances between 2 signal edges are continuously compared to a programmable time window. The maximum count of this edge-to-edge tests before the receiver switches to receiving mode is also programmable.
8.3
Configuring the Bit Check
Assuming a modulation scheme that contains 2 edges per bit, two time frame checks are verifying one bit. This is valid for Manchester, Bi-phase and most other modulation schemes. The maximum count of bits to be checked can be set to 0, 3, 6 or 9 bits via the variable NBit-check in the OPMODE register. This implies 0, 6, 12 and 18 edge-to-edge checks respectively. If NBit-check is set to a higher value, the receiver is less likely to switch to receiving mode due to noise. In the presence of a valid transmitter signal, the bit check takes less time if NBit-check is set to a lower value. In polling mode, the bit-check time is not dependent on NBit-check. Figure 8-2 on page 11 shows an example where 3 bits are tested successfully and the data signal is transferred to pin DATA. According to Figure 8-3, the time window for the bit check is defined by two separate time limits. If the edge-to-edge time t ee i s in between the lower bit-check limit T Lim_min a nd the upper bit-check limit TLim_max, the check will be continued. If tee is smaller than TLim_min or tee exceeds TLim_max, the bit check will be terminated and the receiver switches to sleep mode. Figure 8-3. Valid Time Window for Bit Check
1/fSig tee TLim_min TLim_max
Dem_out
For best noise immunity it is recommended to use a low span between TLim_min and TLim_max. This is achieved using a fixed frequency at a 50% duty cycle for the transmitter preburst. A ‘11111...’ or a ‘10101...’ sequence in Manchester or Bi-phase is a good choice concerning that advice. A good compromise between receiver sensitivity and susceptibility to noise is a time window of ±30% regarding the expected edge-to-edge time t ee. Using pre-burst patterns that contain various edge-to-edge time periods, the bit-check limits must be programmed according to the required span. The bit-check limits are determined by means of the formula below. TLim_min = Lim_min × TXClk TLim_max = (Lim_max – 1) × TXClk Lim_min and Lim_max are defined by a 5-bit word each within the LIMIT register.
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Using above formulas, Lim_min and Lim_max can be determined according to the required TLim_min, TLim_max and TXClk. The time resolution defining TLim_min and TLim_max is TXClk. The minimum edge-to-edge time t ee ( t DATA_L_min , t DATA_H_min ) is defined according to the section “Receiving Mode” on page 14. The lower limit should be set to Lim_min ≥ 10. The maximum value of the upper limit is Lim_max = 63. If the calculated value for Lim_min is < 19, it is recommended to check 6 or 9 bits (NBit-check) to prevent switching to receiving mode due to noise. Figure 8-7 on page 15, Figure 8-8 and Figure 8-9 on page 15 illustrate the bit check for the bit-check limits Lim_min = 14 and Lim_max = 24. When the IC is enabled, the signal processing circuits are enabled during TStartup. The output of the ASK/FSK demodulator (Dem_out) is undefined during that period. When the bit check becomes active, the bit-check counter is clocked with the cycle TXClk. Figure 8-7 on page 15 shows how the bit check proceeds if the bit-check counter value CV_Lim is within the limits defined by Lim_min and Lim_max at the occurrence of a signal edge. In Figure 8-8 on page 15 the bit check fails as the value CV_Lim is lower than the limit Lim_min. The bit check also fails if CV_Lim reaches Lim_max. This is illustrated in Figure 8-9 on page 15. Figure 8-4. Timing Diagram During Bit Check
Bit check ok Bit check ok
(Lim_min = 14, Lim_max = 24) IC_ACTIVE Bit check 1/2 Bit Dem_out Bit-checkcounter
0
1/2 Bit
1/2 Bit
1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 1 2 3 4
TStart-up Start-up mode
TXClk
TBit-check Bit-check mode
Figure 8-5.
Timing Diagram for Failed Bit Check (Condition: CV_Lim < Lim_min)
Bit check failed ( CV_Lim < Lim_min )
(Lim_min = 14, Lim_max = 24) IC_ACTIVE Bit check 1/2 Bit Dem_out Bit-checkcounter
0
1 2 3 4 5 6 1 2 3 4 5 6 7 8 9 10 11 12
0
TStart-up Start-up mode
TBit-check Bit-check mode
TSleep Sleep mode
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Figure 8-6.
Timing Diagram for Failed Bit Check (Condition: CV_Lim ≥ Lim_max)
Bit check failed ( CV_Lim Lim_max )
(Lim_min = 14, Lim_max = 24) IC_ACTIVE Bit check 1/2 Bit Dem_out Bit-checkcounter
0
1 2 3 4 5 6 7 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
0
TStart-up Start-up mode
TBit-check Bit-check mode
TSleep Sleep mode
8.4
Duration of the Bit Check
If no transmitter signal is present during the bit check, the output of the ASK/FSK demodulator delivers random signals. The bit check is a statistical process and TBit-check varies for each check. Therefore, an average value for T Bit-check i s given in the electrical characteristics. T Bit-check depends on the selected baud-rate range and on TClk. A higher baud-rate range causes a lower value for TBit-check resulting in a lower current consumption in polling mode. In the presence of a valid transmitter signal, TBit-check is dependent on the frequency of that signal, fSig, and the count of the checked bits, NBit-check. A higher value for NBit-check thereby results in a longer period for TBit-check requiring a higher value for the transmitter pre-burst TPreburst.
8.5
Receiving Mode
If the bit check was successful for all bits specified by NBit-check, the receiver switches to receiving mode. According to Figure 8-2 on page 11, the internal data signal is switched to pin DATA in that case and the data clock is available after the start bit has been detected (see Figure 9-1 on page 19). A connected microcontroller can be woken up by the negative edge at pin DATA or by the data clock at pin DATA_CLK. The receiver stays in that condition until it is switched back to polling mode explicitly.
8.6
Digital Signal Processing
The data from the ASK/FSK demodulator (Dem_out) is digitally processed in different ways and as a result converted into the output signal data. This processing depends on the selected baud-rate range (BR_Range). Figure 8-7 illustrates how Dem_out is synchronized by the extended clock cycle TXClk. This clock is also used for the bit-check counter. Data can change its state only after TXClk has elapsed. The edge-to-edge time period tee of the Data signal as a result is always an integral multiple of TXClk. The minimum time period between two edges of the data signal is limited to tee ≥ TDATA_min. This implies an efficient suppression of spikes at the DATA output. At the same time it limits the maximum frequency of edges at DATA. This eases the interrupt handling of a connected microcontroller. The maximum time period for DATA to stay Low is limited to T DATA_L_max . This function is employed to ensure a finite response time in programming or switching off the receiver via pin DATA. TDATA_L_max is thereby longer than the maximum time period indicated by the transmitter data stream. Figure 8-9 on page 15 gives an example where Dem_out remains Low after the receiver has switched to receiving mode.
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Figure 8-7. Synchronization of the Demodulator Output
T XClk Clock bit-check counter Dem_out
Data_out (DATA)
tee
Figure 8-8.
Debouncing of the Demodulator Output
Dem_out
Data_out (DATA) tDATA_min tDATA_min t DATA_min
tee
t ee
t ee
Figure 8-9.
Steady L State Limited DATA Output Pattern After Transmission
IC_ACTIVE
Bit check Dem_out
Data_out (DATA) tDATA_min Start-up mode Bit-check mode Receiving mode tDATA_L_max
After the end of a data transmission, the receiver remains active. Depending of the bit Noise_Disable in the OPMODE register, the output signal at pin DATA is high or random noise pulses appear at pin DATA (see section “Digital Noise Suppression” on page 21). The edge-to-edge time period tee of the majority of these noise pulses is equal or slightly higher than TDATA_min.
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8.7
Switching the Receiver Back to Sleep Mode
The receiver can be set back to polling mode via pin DATA or via pin POLLING/_ON. When using pin DATA, this pin must be pulled to Low for the period t1 by the connected microcontroller. Figure 8-10 on page 16 illustrates the timing of the OFF command (see Figure 13-2 on page 28). The minimum value of t1 depends on BR_Range. The maximum value for t1 is not limited but it is recommended not to exceed the specified value to prevent erasing the reset marker. Note also that an internal reset for the OPMODE and the LIMIT register will be generated if t1 exceeds the specified values. This item is explained in more detail in the section “Configuration of the Receiver” on page 23. Setting the receiver to sleep mode via DATA is achieved by programming bit 1 to be ‘1’ during the register configuration. Only one sync pulse (t3) is issued. The duration of the OFF command is determined by the sum of t1, t2 and t10. After the OFF command the sleep time TSleep elapses. Note that the capacitive load at pin DATA is limited (see section “Data Interface” on page 29).
Figure 8-10. Timing Diagram of the OFF Command via Pin DATA
IC_ACTIVE
t1 t2 t3 t4 t10 t7 t5
Out1 (microcontroller)
Data_out (DATA)
X
Serial bi-directional data line
X
Bit 1 ("1") (Start bit) OFF-command Receiving mode TSleep Sleep mode TStart-up Start-up mode
Figure 8-11. Timing Diagram of the OFF Command via Pin POLLING/_ON
IC_ACTIVE ton2 ton3 Bit check ok
POLLING/_ON
Data_out (DATA)
X
X
Serial bi-directional data line
X
X
Receiving mode
Sleep mode
Start-up mode
Bit-check mode
Receiving mode
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Figure 8-12. Activating the Receiving Mode via Pin POLLING/_ON
IC_ACTIVE ton1
POLLING/_ON
Data_out (DATA)
X
Serial bi-directional data line Sleep mode Start-up mode
X
Receiving mode
Figure 8-11 on page 16 illustrates how to set the receiver back to polling mode via pin POLLING/_ON. The pin POLLING/_ON must be held to low for the time period ton2. After the positive edge on pin POLLING/_ON and the delay ton3, the polling mode is active and the sleep time TSleep elapses. This command is faster than using pin DATA at the cost of an additional connection to the microcontroller. Figure 8-12 on page 17 illustrates how to set the receiver to receiving mode via the pin POLLING/_ON. The pin POLLING/_ON must be held to Low. After the delay ton1, the receiver changes from sleep mode to start-up mode regardless the programmed values for TSleep and NBit-check. As long as POLLING/_ON is held to Low, the values for TSleep and NBit-check will be ignored, but not deleted (see section “Digital Noise Suppression” on page 21). If the receiver is polled exclusively by a microcontroller, TSleep must be programmed to 31 (permanent sleep mode). In this case the receiver remains in sleep mode as long as POLLING/_ON is held to High.
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9. Data Clock
The pin DATA_CLK makes a data shift clock available to sample the data stream into a shift register. Using this data clock, a microcontroller can easily synchronize the data stream. This clock can only be used for Manchester and Bi-phase coded signals.
9.1
Generation of the Data Clock
After a successful bit check, the receiver switches from polling mode to receiving mode and the data stream is available at pin DATA. In receiving mode, the data clock control logic (Manchester/Bi-phase demodulator) is active and examines the incoming data stream. This is done, like in the bit check, by subsequent time frame checks where the distance between two edges is continuously compared to a programmable time window. As illustrated in Figure 9-1 on page 19, only two distances between two edges in Manchester and Bi-phase coded signals are valid (T and 2T). The limits for T are the same as used for the bit check. They can be programmed in the LIMIT-register (Lim_min and Lim_max, see Table 11-10 on page 26 and Table 11-11 on page 26). The limits for 2T are calculated as follows: Lower limit of 2T: Upper limit of 2T: Lim_min_2T = (Lim_min + Lim_max) – (Lim_max – Lim_min)/2 Lim_max_2T= (Lim_min + Lim_max) + (Lim_max – Lim_min)/2
(If the result for ’Lim_min_2T’ or ’Lim_max_2T’ is not an integer value, it will be round up) The data clock is available, after the data clock control logic has detected the distance 2T (Start bit) and is issued with the delay tDelay after the edge on pin DATA (see Figure 9-1 on page 19). If the data clock control logic detects a timing or logical error (Manchester code violation), like illustrated in Figure 9-2 on page 19 and Figure 9-3 on page 19, it stops the output of the data clock. The receiver remains in receiving mode and starts with the bit check. If the bit check was successful and the start bit has been detected, the data clock control logic starts again with the generation of the data clock (see Figure 9-4 on page 20). It is recommended to use the function of the data clock only in conjunction with the bit check 3, 6 or 9. If the bit check is set to 0 or the receiver is set to receiving mode via the pin POLLING/_ON, the data clock is available if the data clock control logic has detected the distance 2T (Start bit). Note that for Bi-phase-coded signals, the data clock is issued at the end of the bit.
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Figure 9-1. Timing Diagram of the Data Clock
Preburst Bit check ok T '1' Dem_out '1' '1' '1' '1' 2T '0' '1' '1' '0' '1' '0' Data
Data_out (DATA)
DATA_CLK Start bit Bit-check mode t Delay Receiving mode, data clock control logic active t P_Data_Clk
Figure 9-2.
Data Clock Disappears Because of a Timing Error
Data Timing error
T ee
Tee < TLim_min OR tLim_max < TLim_min_2T or Tee > TLim_max_2T)
'1' Dem_out
'1'
'1'
'1'
'1'
'0'
'1'
'1'
'0'
'1'
'0'
Data_out (DATA)
DATA_CLK Receiving mode, data clock control logic active Receiving mode, bit check active
Figure 9-3.
Data Clock Disappears Because of a Logical Error
Data Logical error (Manchester code violation)
'1' Dem_out
'1'
'1'
'0'
'1'
'1'
'?'
'0'
'0'
'1'
'0'
Data_out (DATA)
DATA_CLK Receiving mode, data clock control logic active Receiving mode, bit check aktive
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Figure 9-4.
Output of the Data Clock After a Successful Bit Check
Da t a Bit check ok
'1' Dem_out
'1'
'1'
'1'
'1'
'0'
'1'
'1'
'0'
'1'
'0'
Data_out (DATA)
DATA_CLK Receiving mode, bit check active
Start bit
Receiving mode, data clock control logic active
The delay of the data clock is calculated as follows: tDelay = tDelay1 + tDelay2 tDelay1 is the delay between the internal signals Data_Out and Data_In. For the rising edge, tDelay1 depends on the capacitive load CL at pin DATA and the external pull-up resistor Rpup. For the falling edge, tDelay1 depends additionally on the external voltage VX (see Figure 9-5, Figure 9-6 on page 21 and Figure 13-2 on page 28). When the level of Data_In is equal to the level of Data_Out, the data clock is issued after an additional delay tDelay2. Note that the capacitive load at pin DATA is limited. If the maximum tolerated capacitive load at pin DATA is exceeded, the data clock disappears (see section “Data Interface” on page 29). Figure 9-5. Timing Characteristic of the Data Clock (Rising Edge on Pin DATA)
Data_Out
VIH = 0.65 VII = 0.35 VX VS VS
Serial bi-directional data line Data_In DATA_CLK tDelay1 tDelay tDelay2 t P_Data_Clk
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Figure 9-6. Timing Characteristic of the Data Clock (Falling Edge of the Pin DATA)
Data_Out
VX VIH = 0.65 VS VII = 0.35 VS
Serial bi-directional data line Data_In DATA_CLK t Delay1 t Delay t Delay2 tP_Data_Clk
10. Digital Noise Suppression
After a data transmission, digital noise appears on the data output (see Figure 10-1 on page 21). Preventing that digital noise keeps the connected microcontroller busy. It can be suppressed in two different ways.
10.1
Automatic Noise Suppression
If the bit Noise_Disable (Table 11-9 on page 25) in the OPMODE register is set to 1 (default), the receiver changes to bit-check mode at the end of a valid data stream. The digital noise is suppressed and the level at pin DATA is High in that case. The receiver changes back to receiving mode, if the bit check was successful. This way to suppress the noise is recommended if the data stream is Manchester or Bi-phase coded and is active after power on. Figure 10-3 on page 22 illustrates the behavior of the data output at the end of a data stream. Note that if the last period of the data stream is a high period (rising edge to falling edge), a pulse occurs on pin DATA. The length of the pulse depends on the selected baud-rate range.
Figure 10-1. Output of Digital Noise at the End of the Data Stream
Bit check ok Preburst Data Digital Noise Bit check ok Digital Noise Preburst Data Digital Noise
Data_out (DATA) DATA_CLK Bit-check mode
Receiving mode, data clock control logic active
Receiving mode, bit check aktive
Receiving mode, data clock control logic active
Receiving mode, bit check aktive
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Figure 10-2. Automatic Noise Suppression
Bit check ok Preburst Da ta Bit check ok Preburst Data
Data_out (DATA) DATA_CLK Bit-check mode
Receiving mode, data clock control logic active
Bit-check mode
Receiving mode, data clock control logic active
Bit-check mode
Figure 10-3. Occurrence of a Pulse at the End of the Data Stream
Timing error tee < TLim_min OR TLim_max < tee < TLim_min_2T OR tee > TLim_max2T
T ee
Data stream
Digital noise
'1' Dem_out
'1'
'1'
Data_out (DATA)
T Pulse
DATA_CLK Receiving mode, data clock control logic active Bit-check mode
10.2
Controlled Noise Suppression by the Microcontroller
If the bit Noise_Disable (see Table 11-9 on page 25) in the OPMODE register is set to 0, digital noise appears at the end of a valid data stream. To suppress the noise, the pin POLLING/_ON must be set to Low. The receiver remains in receiving mode. Then, the OFF command causes the change to the start-up mode. The programmed sleep time (see Table 11-7 on page 25) will not be executed because the level at pin POLLING/_ON is low, but the bit check is active in that case. The OFF command activates the bit check also if the pin POLLING/_ON is held to Low. The receiver changes back to receiving mode if the bit check was successful. To activate the polling mode at the end of the data transmission, the pin POLLING/_ON must be set to High. This way of suppressing the noise is recommended if the data stream is not Manchester or Bi-phase coded.
Figure 10-4. Controlled Noise Suppression
Bit check ok Serial bi-directional data line (DATA_CLK) Preburst Data OFF-command Digital Noise Bit check ok Preburst Data Digital Noise
POLLING/_ON Bit-check mode Receiving mode Start-up Bit-check mode mode Receiving mode Sleep mode
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11. Configuration of the Receiver
The T5760/T5761 receiver is configured via two 12-bit RAM registers called OPMODE and LIMIT. The registers can be programmed by means of the bidirectional DATA port. If the register contents have changed due to a voltage drop, this condition is indicated by a certain output pattern called reset marker (RM). The receiver must be reprogrammed in that case. After a Power-On Reset (POR), the registers are set to default mode. If the receiver is operated in default mode, there is no need to program the registers. Table 11-3 on page 23 shows the structure of the registers. According to Table 11-2, bit 1 defines if the receiver is set back to polling mode via the OFF command (see section “Receiving Mode” on page 14) or if it is programmed. Bit 2 represents the register address. It selects the appropriate register to be programmed. To get a high programming reliability, bit 15 (Stop bit), at the end of the programming operation, must be set to 0.
Table 11-1.
Bit 1 1 0 0
Effect of Bit 1 and Bit 2 on Programming the Registers
Bit 2 x 1 0 Action The receiver is set back to polling mode (OFF command) The OPMODE register is programmed The LIMIT register is programmed
Table 11-2.
0 1
Effect of Bit 15 on Programming the Register
Action The values will be written into the register (OPMODE or LIMIT) The values will not be written into the register
Bit 15
Table 11-3.
Bit 1 Bit 2
Effect of the Configuration Words within the Registers
Bit 3 Bit 4 Bit 5 Bit 6 Bit 7 Bit 8 Bit 9 Bit 10 Bit 11 Bit 12 Bit 13 Bit 14 Bit 15 OFF command
1 –
–
–
–
–
–
–
–
–
–
–
–
–
–
– –
OPMODE register BR_Range NBit-check BitChk1 BitChk0 Modu-lat ion ASK/ _FSK 0 Sleep4 Sleep3 Sleep Sleep2 Sleep1 Sleep0 XSleep XSleepStd Noise Suppression Noise_ Disable 1
0
1 Baud1 Baud0
0
Default values of Bit 3...14 –
0
0
0
1
0
0
1
1
0
0
– –
LIMIT register Lim_min Lim_max Lim_ min1 0 Lim_ min0 1 Lim_ max5 1 Lim_ max4 0 Lim_ max3 1 Lim_ max2 0 Lim_ max1 0 Lim_ max0 1 0
– 0
0
Lim_ min5 0
Lim_ min4 1
Lim_ min3 0
Lim_ min2 1
Default values of Bit 3...14
–
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The following tables illustrate the effect of the individual configuration words. The default configuration is highlighted for each word. BR_Range sets the appropriate baud-rate range and simultaneously defines XLim. XLim is used to define the bit-check limits TLim_min and TLim_max as shown in Table 11-10 on page 26 and Table 11-11 on page 26.
Table 11-4.
Baud1 0
Effect of the configuration word BR_Range
Baud0 0 Baud-rate Range/Extension Factor for Bit-check Limits (XLim) BR_Range0 (application USA/Europe: BR_Range0 = 1.0 kBaud to 1.8 kBaud) XLim = 8 (default) BR_Range1 (application USA/Europe: BR_Range1 = 1.8 kBaud to 3.2 kBaud) XLim = 4 BR_Range2 (application USA/Europe: BR_Range2 = 3.2 kBaud to 5.6 kBaud) XLim = 2 BR_Range3 (Application USA/Europe: BR_Range3 = 5.6 kBaud to 10 kBaud) XLim = 1
BR_Range
0
1
1
0
1
1
Table 11-5.
Effect of the Configuration word NBit-check
NBit-check BitChk0 0 1 0 1 Number of Bits to be Checked 0 3 (default) 6 9
BitChk1 0 0 1 1
Table 11-6.
Effect of the Configuration Bit Modulation
Modulation ASK/_FSK 0 1 Selected Modulation – FSK (default) ASK
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Table 11-7.
Sleep4 0 0 0 0 ... 0 ... 1 1 1
Effect of the Configuration Word Sleep
Sleep Sleep3 0 0 0 0 ... 0 ... 1 1 1 Sleep2 0 0 0 0 ... 1 ... 1 1 1 Sleep1 0 0 1 1 ... 1 ... 0 1 1 Sleep0 0 1 0 1 ... 0 ... 1 0 1 Start Value for Sleep Counter (TSleep = Sleep × XSleep × 1024 × TClk) 0 (Receiver is continuously polling until a valid signal occurs) 1 (TSleep ≈ 2.1 ms for XSleep = 1 and fRF = 868.3 ms, ≈ 2.0 ms for fRF = 915 MHz) 2 3 ... 6 (TSleep = 12.695 ms for fRF = 868.3 MHz, 12.047 ms for fRF = 915 MHz) (default) ... 29 30 31 (permanent sleep mode)
Table 11-8.
Effect of the Configuration Bit XSleep
XSleep XSleepStd 0 1 Extension Factor for Sleep Time (TSleep = Sleep × XSleep × 1024 × TClk) 1 (default) 8
Table 11-9.
Effect of the Configuration Bit Noise Suppression
Suppression of the Digital Noise at Pin DATA
Noise suppression is inactive Noise suppression is active (default)
Noise Suppression Noise_Disable
0 1
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Table 11-10. Effect of the Configuration Word Lim_min
Lim_min(1) (Lim_min < 10 is not Applicable) Lim_min5 0 0 0 .. Lim_min4 0 0 0 .. Lim_min3 1 1 1 .. Lim_min2 0 0 1 .. Lim_min1 1 1 0 .. Lim_min0 0 1 0 .. 21 (default) (TLim_min = 347 µs for fRF = 868.3 MHz and BR_Range0 TLim_min = 329 µs for fRF = 915 MHz and BR_Range0) 61 62 63 Lower Limit Value for Bit Check (TLim_min = Lim_min × XLim × TClk) 10 11 12
0
1
0
1
0
1
.. 1 1 1 Note:
.. 1 1 1
.. 1 1 1
.. 1 1 1
.. 0 1 1
.. 1 0 1
1. Lim_min is also used to determine the margins of the data clock control logic (see section “Data Clock” on page 18).
Table 11-11. Effect of the Configuration Word Lim_max
Lim_max(1) (Lim_max < 12 is not applicable) Lim_max5 0 0 0 .. Lim_max4 0 0 0 .. Lim_max3 1 1 1 .. Lim_max2 1 1 1 .. Lim_max1 0 0 1 .. Lim_max0 0 1 0 .. 41 (default) (TLim_max = 661 µs for fRF = 868.3 MHz and BR_Range0, TLim_max = 627 µs for fRF = 915 MHz and BR_Range0) 61 62 63 Upper Limit Value for Bit Check (TLim_max = (Lim_max – 1) × XLim × TClk) 12 13 14
1
0
1
0
0
1
.. 1 1 1 Note:
.. 1 1 1
.. 1 1 1
.. 1 1 1
.. 0 1 1
.. 1 0 1
1. Lim_max is also used to determine the margins of the data clock control logic (see section “Data Clock” on page 18).
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12. Conservation of the Register Information
The ATA5760/ATA5761 implies an integrated power-on reset and brown-out detection circuitry to provide a mechanism to preserve the RAM register information. According to Figure 12-1, a power-on reset (POR) is generated if the supply voltage VS drops below the threshold voltage VThReset. The default parameters are programmed into the configuration registers in that condition. Once VS exceeds VThReset the POR is canceled after the minimum reset period tRst. A POR is also generated when the supply voltage of the receiver is turned on. To indicate that condition, the receiver displays a reset marker (RM) at pin DATA after a reset. The RM is represented by the fixed frequency fRM at a 50% duty-cycle. RM can be canceled via a Low pulse t1 at pin DATA. The RM implies the following characteristics: • fRM is lower than the lowest feasible frequency of a data signal. By this means, RM cannot be misinterpreted by the connected microcontroller. • If the receiver is set back to polling mode via pin DATA, RM cannot be canceled by accident if t1 is applied according to the proposal in the section “Programming the Configuration Register” on page 28. By means of that mechanism the receiver cannot lose its register information without communicating that condition via the reset marker RM. Figure 12-1. Generation of the Power-on Reset
VS POR tRst Data_out (DATA) X
V ThReset
1/fRM
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13. Programming the Configuration Register
Figure 13-1. Timing of the Register Programming
IC_ACTIVE t1 t2 t3 t4 Out1 (microcontroller) t5 t6 t7 t9 t8
Data_out (DATA)
X
Serial bi-directional data line
X Bit 1 ("0") (Start bit) Bit 2 ("1") (Registerselect) Programming frame Receiving mode Bit 14 ("0") (Poll8) Bit 15 ("0") (Stop bit) TSleep TStart-up Sleep Start-up mode mode
Figure 13-2. Data Interface
V X = 5 V to 20 V VS = 4.5 V to 5.5 V
ATA5760/ ATA5761
Rpup DATA I/O
Serial bi-directional data line
Microcontroller
0 V/5 V
Data_In
Input Interface
0 ... 20 V
ID
CL
Data_out
Out1 (microcontroller )
The configuration registers are programmed serially via the bi-directional data line according to Figure 13-1 and Figure 13-2. To start programming, the serial data line DATA is pulled to Low for the time period t1 by the microcontroller. When DATA has been released, the receiver becomes the master device. When the programming delay period t2 has elapsed, it emits 15 subsequent synchronization pulses with the pulse length t3. After each of these pulses, a programming window occurs. The delay until the program window starts is determined by t4, the duration is defined by t5. Within the programming window, the individual bits are set. If the microcontroller pulls down pin DATA for the time period t7 during t5, the according bit is set to ’0’. If no programming pulse t7 is issued, this bit is set to ’1’. All 15 bits are subsequently programmed this way. The time frame to program a bit is defined by t6.
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Bit 15 is followed by the equivalent time window t9. During this window, the equivalence acknowledge pulse t8 (E_Ack) occurs if the just programmed mode word is equivalent to the mode word that was already stored in that register. E_Ack should be used to verify that the mode word was correctly transferred to the register. The register must be programmed twice in that case. Programming of a register is possible both in sleep-mode and in active-mode of the receiver. During programming, the LNA, LO, lowpass filter IF-amplifier and the FSK/ASK Manchester demodulator are disabled. The programming start pulse t1 initiates the programming of the configuration registers. If bit 1 is set to ’1’, it represents the OFF command to set the receiver back to polling mode at the same time. For the length of the programming start pulse t1, the following convention should be considered: • t1(min) < t1 < 5632 TClk: t1(min) is the minimum specified value for the relevant BR_Range Programming respectively OFF command is initiated if the receiver is not in reset mode. If the receiver is in reset mode, programming respectively Off command is not initiated and the reset marker RM is still present at pin DATA. This period is generally used to switch the receiver to polling mode or to start the programming of a register. In reset condition, RM is not cancelled by accident. • t1 > 7936 × TClk Programming respectively OFF command is initiated in any case. The registers OPMODE and LIMIT are set to the default values. RM is cancelled if present. This period is used if the connected microcontroller detected RM. If the receiver operates in default mode, this time period for t1 can generally be used. Note that the capacitive load at pin DATA is limited.
14. Data Interface
The data interface (see Figure 13-2 on page 28) is designed for automotive requirements. It can be connected via the pull-up resistor Rpup up to 20V and is short-circuit-protected. The applicable pull-up resistor R pup d epends on the load capacity C L a t pin DATA and the selected BR_range (see Table 14-1).
Table 14-1.
-
Applicable Rpup
BR_range B0 B1 B2 B3 B0 B1 B2 B3 Applicable Rpup 1.6 kΩ to 47 kΩ 1.6 kΩ to 22 kΩ 1.6 kΩ to 12 kΩ 1.6 kΩ to 5.6 kΩ 1.6 kΩ to 470 kΩ 1.6 kΩ to 220 kΩ 1.6 kΩ to 120 kΩ 1.6 kΩ to 56 kΩ
CL ≤ 1nF
CL ≤ 100pF
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Figure 14-1. Application Circuit: fRF = 868.3 MHz without SAW Filter
VS C7 4.7u 10% GND R3 >= 1.6k C14 39n 5% C13 10n 10%
1 SENS 2 IC_ACTIVE 3 CDEM 4 AVCC 5 TEST1 6 AGND 7 n.c. DATA POLLING/_ON DGND DATA_CLK TEST4 DVCC 20 19 18 17 16 15
IC_ACTIVE R2 Sensitivity reduction 56k to 150k VX = 5 V to 20 V
DATA POLLING/_ON DATA_CLK C12 10n 10% C11
ATA5760
Q1
14
XTAL
12p 2% np0
8 LNAREF 9 LNA_IN 10 LNAGND
n.c. 13 12 TEST3 11 TEST2
6.77617 MHz for BIF = 600 kHz 6.77587 MHz for BIF = 300 kHz
RF_IN
C17 1.5p ±0.1p np0
C16 18p 5% np0 Toko LL1608-FS4N7S 4.7nH, ±0.3nH
Figure 14-2. Application Circuit: fRF = 868.3 MHz with SAW Filter
VS C7 4.7µ 10% GND
1 SENS 2 IC_ACTIVE 3 CDEM 4 AVCC 5 TEST1 6 AGND 7 NC DATA POLLING/_ON DGND DATA_CLK TEST4 DVCC XTAL 20 19 18 17 16 15
IC_ACTIVE R2 Sensitivity reduction 56k to 150k R3 1.6k C14 39n 5% C13 10n 10% VX = 5 V to 20 V
DATA POLLING/_ON DATA_CLK C12 10n 10% C11 12p 2% np0
ATA5760
Q1
14
8 LNAREF 9 LNA_IN 10 LNAGND
NC 13 12 TEST3 11 TEST2
6.77617 MHz for BIF = 600 kHz 6.77587 MHz for BIF = 300 kHz
C16 18p 5% np0
C17 5.6p ±0.1p np0 Toko LL1608-FS4N7S 4.7nH, ±0.3nH
5 6 7 8
RF_IN
Toko LL1608-FS12NJ 12 nH, 5% 1 2 C2 3 3.3p 4 ±0.1p np0
EPCOS B3570 IN IN_GND CASE_GND CASE_GND OUT OUT_GND CASE_GND CASE_GND
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15. Absolute Maximum Ratings
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Parameters Supply voltage Power dissipation Junction temperature Storage temperature Ambient temperature Maximum input level, input matched to 50Ω Symbol VS Ptot Tj Tstg Tamb Pin_max –55 –40 Min. Max. 6 1000 150 +125 +105 10 Unit V mW °C °C °C dBm
16. Thermal Resistance
Parameters Junction ambient Symbol RthJA Value 100 Unit K/W
17. Electrical Characteristics
All parameters refer to GND, Tamb = –40°C to +105°C, VS = 4.5V to 5.5V, f0 = 868.3 MHz and f0 = 915 MHz, unless otherwise specified. (For typical values: VS = 5V, Tamb = 25°C)
fRF = 868.3 MHz Parameter Test Conditions Symbol Min. Typ. Max. Min. Basic Clock Cycle of the Digital Circuitry Basic clock cycle Extended basic clock cycle Polling Mode Sleep time (see Figure 8-4 on page 13, Figure 9-1 on page 19 and Figure 14-1 on page 30) Start-up time (see Figure 8-4 on page 13 and Figure 8-5 on page 13) BR_Range0 BR_Range1 BR_Range2 BR_Range3 TClk 2.0662 16.53 8.26 4.13 2.07 2.0662 16.53 8.26 4.13 2.07 1.9607 15.69 7.84 3.92 1.96 1.9607 15.69 7.84 3.92 1.96 14/fXTO 8× 4× 2× 1× TClk TClk TClk TClk 14/fXTO 8× 4× 2× 1× TClk TClk TClk TClk µs µs µs µs µs fRF = 915 MHz Typ. Max. Min. Variable Oscillator Typ. Max. Unit
TXClk
Sleep and XSleep are defined in the OPMODE register
TSleep
Sleep × XSleep × 1024 × 2.0662
Sleep × XSleep × 1024 × 2.0662
Sleep × XSleep × 1024 × 1.9607
Sleep × XSleep × 1024 × 1.9607
Sleep × XSleep × 1024 × TClk
Sleep × XSleep × 1024 × TClk
ms
BR_Range0 BR_Range1 BR_Range2 BR_Range3
TStartup
1852 1059 1059 662
1852 1059 1059 662
1758 1049 1049 628
1758 1049 1049 628
896.5 512.5 512.5 320.5 × TClk
896.5 512.5 512.5 320.5 × TClk
µs µs µs µs µs
31
4896D–RKE–08/08
17. Electrical Characteristics (Continued)
All parameters refer to GND, Tamb = –40°C to +105°C, VS = 4.5V to 5.5V, f0 = 868.3 MHz and f0 = 915 MHz, unless otherwise specified. (For typical values: VS = 5V, Tamb = 25°C)
fRF = 868.3 MHz Parameter Test Conditions Symbol Min. Typ. Max. Min. Average bit-check time while polling, no RF applied Time for bit (see Figure 8-8 on page 15 and check (see Figure 8-4 on Figure 8-9 on page 15) page 13) BR_Range0 BR_Range1 BR_Range2 BR_Range3 Bit-check time for a valid input signal fSig (see Time for bit Figure 8-5 on check (see page 13) Figure 8-4 on NBit-check = 0 page 13) NBit-check = 3 NBit-check = 6 NBit-check = 9 Receiving Mode Intermediate frequency Baud-rate range Minimum time period between edges at pin DATA (see Figure 8-11 and Figure 8-12 on page 17) (With the exception of parameter TPulse) Maximum Low period at pin DATA (see Figure 8-9 on page 15) Delay to activate the start-up mode (see Figure 9-3 on page 19) BR_Range0 BR_Range1 BR_Range2 BR_Range3 fIF 1.0 1.8 3.2 5.6 0.95 1.8 3.2 5.6 10.0 1.054 1.89 3.38 5.9 1.00 1.89 3.38 5.9 10.5 fRF/915 BR_Range0 × BR_Range1 × BR_Range2 × BR_Range3 × 2 µs/TClk 2 µs/TClk 2 µs/TClk 2 µs/TClk MHz kBaud kBaud kBaud kBaud fRF = 915 MHz Typ. Max. Min. Variable Oscillator Typ. Max. Unit
TBit-check 0.45 0.24 0.14 0.08 0.45 0.24 0.14 0.08 ms ms ms ms
TBit-check 3/fSig 6/fSig 9/fSig 3.5/fSig 6.5/fSig 9.5/fSig 3/fSig 6/fSig 9/fSig 3.5/fSig 6.5/fSig 9.5/fSig
1 × TXClk 3/fSig 6/fSig 9/fSig
1 × TClk 3.5/fSig 6.5/fSig 9.5/fSig
ms ms ms ms
BR_Range
BR_Range = BR_Range0 BR_Range1 BR_Range2 BR_Range3 165.3 82.6 41.3 20.7 165.3 82.6 41.3 20.7 156.8 78.4 39.2 19.6 156.8 78.4 39.2 19.6 10 × 10 × 10 × 10 × TXClk TXClk TXClk TXClk 10 × 10 × 10 × 10 × TXClk TXClk TXClk TXClk µs µs µs µs
tDATA_min
BR_Range = BR_Range0 BR_Range1 BR_Range2 BR_Range3
tDATA_L_max
2149 1074 537 269
2149 1074 537 269
2139 1020 510 255
2139 1020 510 255
130 × 130 × 130 × 130 ×
TXClk TXClk TXClk TXClk
130 × 130 × 130 × 130 ×
TXClk TXClk TXClk TXClk
µs µs µs µs
Ton1
19.6
21.7
18.6
20.6
9.5 × TClk
10.5 × TClk
µs
32
ATA5760/ATA5761
4896D–RKE–08/08
ATA5760/ATA5761
17. Electrical Characteristics (Continued)
All parameters refer to GND, Tamb = –40°C to +105°C, VS = 4.5V to 5.5V, f0 = 868.3 MHz and f0 = 915 MHz, unless otherwise specified. (For typical values: VS = 5V, Tamb = 25°C)
fRF = 868.3 MHz Parameter OFF command at pin POLLING/_O N (see Figure 9-2 on page 19) Delay to activate the sleep mode (see Figure 9-2 on page 19) Pulse on pin DATA at the end of a data stream (see Figure 12-1 on page 27) BR_Range = BR_Range0 BR_Range1 BR_Range2 BR_Range3 Test Conditions Symbol Min. Typ. Max. Min. fRF = 915 MHz Typ. Max. Min. Variable Oscillator Typ. Max. Unit
Ton2
16.5
15.6
8 × TClk
µs
Ton3
17.6
19.6
16.6
18.6
8.5 × TClk
9.5 × TClk
µs
TPulse
16.5 8.3 4.1 2.1
16.5 8.3 4.1 2.1
15.69 7.84 3.92 1.96
15.69 7.84 3.92 1.96
8× 4× 2× 1×
TClk TClk TClk TClk
8× 4× 2× 1×
TClk TClk TClk TClk
µs µs µs µs
Configuration of the Receiver (see Figure 8-10 on page 16 and Figure 14-1 on page 30) Frequency of Frequency is stable within the reset 50 ms after POR marker BR_Range = BR_Range0 Programming BR_Range1 BR_Range2 start pulse BR_Range3 after POR Programming delay period Synchroni-zat ion pulse Delay until of the program window starts Programming window Time frame of a bit Programming pulse Equivalent acknowledge pulse: E_Ack Equivalent time window OFF-bit programming window fRM 118.2 118.2 124.5 124.5 1/ (4096 × TClk) 1624 × TClk 1100 × TClk 838 × TClk 707 × TClk 7936 × TClk 756 251 384.5 × TClk 128 × TClk 63.5 × TClk 256 × TClk 512 × TClk 64 × TClk 128 × TClk 258 × TClk 449.5 × TClk 1/ (4096 × TClk) 5632 × 5632 × 5632 × 5632 × TClk TClk TClk TClk Hz
t1
3355 2273 1731 1461 16397 795 264
11637 11637 11637 11637
3184 2168 1643 1386 15560 754 251
11043 11043 11043 11043
µs µs µs µs µs µs µs
t2 t3
797 264
385.5 × TClk 128 × TClk 63.5 × TClk 256 × TClk 512 × TClk 256 × TClk 128 × TClk 258 × TClk 449.5 × TClk
t4
131
131
125
125
µs
t5 t6 t7
529 1058 132
529 1058 529
502 1004 125
502 1004 502
µs µs µs
t8
264
264
251
251
µs
t9
533
533
506
506
µs
t10
929
929
881
881
µs
33
4896D–RKE–08/08
17. Electrical Characteristics (Continued)
All parameters refer to GND, Tamb = –40°C to +105°C, VS = 4.5V to 5.5V, f0 = 868.3 MHz and f0 = 915 MHz, unless otherwise specified. (For typical values: VS = 5V, Tamb = 25°C)
fRF = 868.3 MHz Parameter Test Conditions Symbol Min. Typ. Max. Min. Data Clock (see Figure 10-2 on page 22 and Figure 10-3 on page 22) Minimum delay time between edge at DATA and DATA_CLK Pulse width of negative pulse at pin DATA_CLK BR_Range = BR_Range0 BR_Range1 BR_Range2 BR_Range3 BR_Range = BR_Range0 BR_Range1 BR_Range2 BR_Range3 0 0 0 0 16.5 8.3 4.1 2.1 0 0 0 0 16.7 7.8 3.9 1.96 0 0 0 0 1× 1× 1× 1× TXClk TXClk TXClk TXClk µs µs µs µs fRF = 915 MHz Typ. Max. Min. Variable Oscillator Typ. Max. Unit
tDelay2
tP_DATA_CLK
66.1 33.0 16.5 8.3
66.1 33.0 16.5 8.3
63 31 15.7 7.8
63 31 15.7 7.8
4× 4× 4× 4×
TXClk TXClk TXClk TXClk
4× 4× 4× 4×
TXClk TXClk TXClk TXClk
µs µs µs µs
18. Electrical Characteristics (continued)
All parameters refer to GND, Tamb = –40°C to +105°C, VS = 4.5V to 5.5V, f0 = 868.3 MHz and f0 = 915 MHz, unless otherwise specified. (For typical values: VS = 5V, Tamb = 25°C) Parameters Test Conditions Sleep mode (XTO and polling logic active) Current consumption IC active (start-up-, bit-check-, receiving mode) Pin DATA = H FSK ASK LNA/mixer/IF amplifier Required according to I-ETS 300220 With power matching |S11| < –10 dB At 868.3 MHz At 915 MHz Within the complete image band BER ≤ 10 , FSK mode ASK mode
-3
Symbol ISoff
Min.
Typ. 170
Max. 276
Unit µA
ISon
7.8 7.4 –16 –70 5 200 || 3.2 200 || 3.2 –25 20 30
9.9 9.6
mA mA dBm
LNA, Mixer, Polyphase Lowpass and IF Amplifier (Input Matched According to Figure 14-1 on page 30 Referred to RFIN) Third-order intercept point LO spurious emission System noise figure LNA_IN input impedance 1 dB compression point Image rejection Maximum input level IIP3 ISLORF NF ZiLNA_IN IP1db –57 dBm dB Ω || pF Ω || pF dBm dB –10 –10 dBm dBm
Pin_max
34
ATA5760/ATA5761
4896D–RKE–08/08
ATA5760/ATA5761
18. Electrical Characteristics (continued)
All parameters refer to GND, Tamb = –40°C to +105°C, VS = 4.5V to 5.5V, f0 = 868.3 MHz and f0 = 915 MHz, unless otherwise specified. (For typical values: VS = 5V, Tamb = 25°C) Parameters Local Oscillator Operating frequency range VCO Phase noise local oscillator Spurious of the VCO T5760 T5761 fosc = 867.3 MHz at 10 MHz At ±fXTO XTO pulling, appropriate load capacitance must be connected to XTAL, crystal CM = 7 fF Parameter of the supplied crystal Parameter of the supplied crystal and board parasitics ASK (level of carrier) 300 kHz IF-filter BER ≤ 10-3, 100% Mod fin = 868.3 MHz/915 MHz VS = 5V, Tamb = 25°C fIF = 950 kHz/1 MHz BR_Range0 BR_Range1 BR_Range2 BR_Range3 ASK (level of carrier) 600 kHz IF-filter BER ≤ 10-3, 100% Mod fin = 868.3 MHz/915 MHz VS = 5V, Tamb = 25°C fIF = 950 kHz/1 MHz BR_Range0 BR_Range1 BR_Range2 BR_Range3 Sensitivity variation ASK for the full fin = 868.3 MHz/915 MHz operating range compared to Tamb = fIF = 950 kHz/989 kHz/1 MHz 25°C, VS = 5V PASK = PRef_ASK + ΔPRef ΔPRef fVCO fVCO L (fm) 866 900 –140 –55 871 929 –130 –45 MHz MHz dBC/Hz dBC Test Conditions Symbol Min. Typ. Max. Unit
XTO pulling
fXTO RS C0
–30ppm
fXTAL
+30ppm
MHz Ω pF
Series resonance resistor of the crystal Static capacitance at pin XTAL to GND
120 6.5
Analog Signal Processing (Input Matched According to Figure 14-1 on page 30 Referred to RFIN)
Input sensitivity ASK
PRef_ASK –111 –109 –108 –106 –113 –111 –110 –108 –115 –113 –112 –110 dBm dBm dBm dBm
Input sensitivity ASK
PRef_ASK –110 –108.5 –108 –106 +2.5 –112 –110.5 –110 –108 –114 –112.5 –112 –110 –1.0 dBm dBm dBm dBm dB
35
4896D–RKE–08/08
18. Electrical Characteristics (continued)
All parameters refer to GND, Tamb = –40°C to +105°C, VS = 4.5V to 5.5V, f0 = 868.3 MHz and f0 = 915 MHz, unless otherwise specified. (For typical values: VS = 5V, Tamb = 25°C) Parameters Test Conditions 300 kHz version fin = 868.3 MHz/915 MHz fIF = 950 kHz/989 kHz/1 MHz fIF –110 kHz to +110 kHz fIF –140 kHz to +140 kHz PASK = PRef_ASK + ΔPRef 600 kHz version fin = 868.3 MHz/915 MHz fIF = 950 kHz/989 kHz/1 MHz fIF –210 kHz to +210 kHz fIF –270 kHz to +270 kHz PASK = PRef_ASK + ΔPRef BER ≤ 10-3 fin = 868.3 MHz/915 MHz VS = 5V, Tamb = 25°C fIF = 950 kHz/989 kHz/1 MHz BR_Range0 df = ±16 kHz to ±28 kHz df = ±10 kHz to ±100 kHz Input sensitivity FSK 300 kHz and 600 kHz version BR_Range1 df = ±16 kHz to ±28 kHz df = ±10 kHz to ±100 kHz BR_Range2 df = ±18 kHz to ±31 kHz df = ±13 kHz to ±100 kHz BR_Range3 df = ±25 kHz to ±44 kHz df = ±20 kHz to ±100 kHz Sensitivity variation FSK for the full fin = 868.3 MHz/915 MHz operating range compared to Tamb = fIF = 950 kHz/989 kHz/1 MHz 25°C, VS = 5V PFSK = PRef_FSK + ΔPRef 300 kHz version fin = 868.3 MHz/915 MHz fIF = 950 kHz/989 kHz/1 MHz fIF –110 kHz to +110 kHz fIF –140 kHz to +140 kHz Sensitivity variation FSK for the full fIF –180 kHz to +180 kHz PFSK = PRef_FSK + ΔPRef operating range including IF filter compared to Tamb = 25°C, 600 kHz version VS = 5V fin = 868.3 MHz/915 MHz fIF = 950 kHz/989 kHz/1 MHz fIF –150 kHz to +150 kHz fIF –200 kHz to +200 kHz fIF –260 kHz to +260 kHz PFSK = PRef_FSK + ΔPRef S/N ratio to suppress inband noise signals. Noise signals may have any modulation scheme Dynamic range RSSI amplifier ASK mode FSK mode PRef_FSK –103 –101 –101 –99 –99.5 –97.5 –97.5 –95.5 +3 –106 –107.5 –107.5 –105.5 –105.5 –104 dBm dBm dBm dBm dBm dBm dBm dBm dB Symbol Min. Typ. Max. Unit
ΔPRef
+5.5 +7.5
–1.5 –1.5
dB dB
Sensitivity variation ASK for full operating range including IF filter compared to Tamb = 25°C, VS = 5V
ΔPRef
+5.5 +7.5
–1.5 –1.5
dB dB
PRef_FSK
–104
PRef_FSK
–102.5
PRef_FSK
–100.5
–102
ΔPRef
–1.5
ΔPRef
+6 +8 +11
–2 –2 –2
dB dB dB
ΔPRef
+6 +8 +11
–2 –2 –2
dB dB dB
SNRASK SNRFSK ΔRRSSI
10 2 60
12 3
dB dB dB
36
ATA5760/ATA5761
4896D–RKE–08/08
ATA5760/ATA5761
18. Electrical Characteristics (continued)
All parameters refer to GND, Tamb = –40°C to +105°C, VS = 4.5V to 5.5V, f0 = 868.3 MHz and f0 = 915 MHz, unless otherwise specified. (For typical values: VS = 5V, Tamb = 25°C) Parameters Test Conditions Symbol fcu_DF Min. 0.11 Typ. 0.16 39 22 12 8.2 270 156 89 50 1000 560 320 180 Max. 0.20 Unit kHz nF nF nF nF µs µs µs µs
1 Lower cut-off frequency of the data f cu_DF = -----------------------------------------------------------2 × π × 30 k Ω × CDEM filter CDEM = 33 nF Recommended CDEM for best performance BR_Range0 (default) BR_Range1 BR_Range2 BR_Range3 BR_Range0 (default) BR_Range1 BR_Range2 BR_Range3 Upper cut-off frequency programmable in 4 ranges via a serial mode word BR_Range0 (default) BR_Range1 BR_Range2 BR_Range3 300 kHz IF-filter RSense connected from pin Sens to VS, input matched according to Figure 14-1 on page 30, fin = 868.3 MHz/915 MHz, VS = 5V, Tamb = +25°C RSense = 56 kΩ Reduced sensitivity RSense = 100 kΩ 600 kHz IF-filter RSense connected from pin Sens to VS, input matched according to Figure 14-1 on page 30, fin = 868.3 MHz/915 MHz, VS = 5V, Tamb = +25°C RSense = 56 kΩ RSense = 100 kΩ Reduced sensitivity variation over full operating range RSense = 56 kΩ RSense = 100 kΩ PRed = PRef_Red + ΔPRed Values relative to RSense = 56 kΩ RSense = 56 kΩ RSense = 68 kΩ RSense = 82 kΩ RSense = 100 kΩ RSense = 120 kΩ RSense = 150 kΩ PRed = PRef_Red + ΔPRed
CDEM
Edge-to-edge time period of the input data signal for full sensitivity
tee_sig
Upper cut-off frequency data filter
fu
2.8 4.8 8.0 15.0
3.4 6.0 10.0 19.0
4.0 7.2 12.0 23.0
kHz kHz kHz kHz
dBm (peak level)
PRef_Red PRef_Red
–67 –76
–72 –81
–77 –86
dBm dBm
dBm (peak level)
PRef_Red PRef_Red ΔPRed
–63 –72 5 5
–68 –77 0 0
–73 –82 0 0
dBm dBm dB dB
Reduced sensitivity variation for different values of RSense
ΔPRed
0 –3.5 –6.0 –9.0 –11.0 –13.5 1.95 2.8 3.75
dB dB dB dB dB dB V
Threshold voltage for reset
VThRESET
37
4896D–RKE–08/08
18. Electrical Characteristics (continued)
All parameters refer to GND, Tamb = –40°C to +105°C, VS = 4.5V to 5.5V, f0 = 868.3 MHz and f0 = 915 MHz, unless otherwise specified. (For typical values: VS = 5V, Tamb = 25°C) Parameters Digital Ports Data output - Saturation voltage Low - max voltage at pin DATA - quiescent current - short-circuit current - ambient temp. in case of permanent short-circuit Data input - Input voltage Low - Input voltage High DATA_CLK output - Saturation voltage Low - Saturation voltage High IC_ACTIVE output - Saturation voltage Low - Saturation voltage High POLLING/_ON input - Low level input voltage - High level input voltage TEST 4 pin - High level input voltage TEST 1 pin - Low level input voltage Iol ≤ 12 mA Iol = 2 mA Voh = 20V Vol = 0.8V to 20V Voh = 0V to 20V Vol Vol Voh Iqu Iol_lim tamb_sc 13 0.35 0.08 0.8 0.3 20 20 45 85 0.35 × VS V V V µA mA °C Test Conditions Symbol Min. Typ. Max. Unit
30
VIl Vich IDATA_CLK = 1mA IDATA_CLK = –1mA IIC_ACTIVE = 1 mA IIC_ACTIVE = –1 mA Receiving mode Polling mode Test input must always be set to High Test input must always be set to Low Vol Voh Vol Voh VIl VIh VIh VIl
0.65 × VS 0.1 VS – 0.4V VS – 0.15V 0.1 VS – 0.4 V VS – 0.15 V
V V V V V V V V V
0.4
0.4
0.8 × VS 0.8 × VS
0.2 × VS
0.2 × VS
V
38
ATA5760/ATA5761
4896D–RKE–08/08
ATA5760/ATA5761
19. Ordering Information
Extended Type Number ATA5760N-TGSY ATA5760N-TGQY ATA5761N-TGSY ATA5761N-TGQY ATA5760N3-TGQY Package SO20 SO20 SO20 SO20 SO20 Remarks Tube, for 868 MHz ISM band, Pb-free, BIF = 600 kHz Taped and reeled, for 868 MHz ISM band, Pb-free, BIF = 600 kHz Tube, for 915 MHz ISM band, Pb-free, BIF = 600 kHz Taped and reeled, for 915 MHz ISM band, Pb-free, BIF = 600 kHz Taped and reeled, for 868 MHz ISM band, Pb-free, BIF = 300 kHz
20. Package Information
Package SO20
Dimensions in mm
12.95 12.70 9.15 8.65 7.5 7.3
2.35 0.25 10.50 10.20 11
0.4 1.27 11.43 20
0.25 0.10
technical drawings according to DIN specifications
1
10
39
4896D–RKE–08/08
21. Revision History
Please note that the following page numbers referred to in this section refer to the specific revision mentioned, not to this document. Revision No. 4896D-RKE-08/08 History • Put datasheet in the newest template • Page 37: Section 18 “Electrical Characteristics” changed • • • • • • • • • • • • • • • • Page 4: first paragraph changed Page 5: text changed Page 4.1 IF Filter: text changed Page 10: text changed Page 30: figures 14-1 and 14-2 changed Page 31: El.Char. Table: heading row changed Page 35-36: Test condition values changed Page 1: PB-free logo deleted Page 1: Features changed Page 4: RF Front End - text changed Page 5: IF Filter - text changed Page 7: Receiving Characteristics - text changed Page 7: Fig.5-1 - Title text changed Page 8: Fig.5-2 - Title text changed Pages 33 to 37: some lines changed Page 38: Ordering Information table changed
4896C-RKE-04/06
4896B-RKE-02/06
40
ATA5760/ATA5761
4896D–RKE–08/08
Headquarters
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4896D–RKE–08/08
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