AMIS-52000 Single-Chip Radio Transceiver Data Sheet 1.0 Introduction connected to separate antennas for antenna diversity applications. The AMIS-52000 is a low cost, ultra low power ASK/OOK (Amplitude Shift Keying/On-Off Shift Keying) transceiver intended for narrow band RF applications. The device is targeted for applications at 433MHz but can operate from 260 to 700MHz. The adjustable RF output ranges from –26 to +6dBm into a matched 50ohm load. The receiver contains two independent receive channels which can be On chip trim registers eliminate manual trimming of external components. Using the on chip trimming, transmit and receive frequencies achieve 5ppm accuracy over the entire voltage and temperature range. 2.0 Key Features • Very low power single-chip transceiver • Minimal external components • Low power RC oscillator • Unique Quick Start, low-noise oscillator (patent pending) • Extreme low power RF Sniff Mode™, wake on RSSI • Internal trim functions • I2C control interface • Serial TX/RX data port • Clock generation for an external microprocessor • Wake up on RSSI • Unique antenna diversity dual receiver (patent pending) • Internal VCO/PLL tuning varactor 3.0 Technical Features • Sniff Mode Polling: 0.5ms to 16s (0.5ms or 64ms steps) • PLL Lock Time: <50µs • Selectable Data Filter: up to 19.2 Kbps • Internal Trim Function: • TX power • Antenna for trim or tune (2 inputs are independent) • Xtal for frequency and quick start • RC for frequency • Sniff mode for data threshold • Data slice • I2C Interface: Control bus • Serial Interface: Data input/output • Low Frequency IF • Internal IF Filtering • Package: 20-lead, 209 m SSOP • Operating Frequency: Range 260 to 700MHz • TX Output Power: +6dBm • RX Sensitivity: • Sniff Mode: -93dBm minimum • Receive: -103dBm minimum @ 1Kbps • Data Rate: 1 to 19.2Kbps, user selectable • Power Requirements: • Receive: 7.5mA (continuous) • Transmit: 25mA full power; 50% duty cycle • Sniff Mode: 750µA at a 1ms sniff rate (10% duty cycle) • Standby: 500nA (RC oscillator running) • Operating Voltage: 2.4 to 3.6V • Modulation: ASK/OOK (Amplitude Shift Key/On-Off Shift Key) • Xtal Start Time: 15µs (Quick Start) AMI Semiconductor - Confidential www.amis.com 1 AMIS-52000 Single-Chip Radio Transceiver 4.0 Operating and Maximum Specifications Table 1: Operating Conditions Sym VDD Vss Temp Parameter Positive Supply Ground Temperature Range Min 2.4 Typ 3.0 0.0 +25 0 Max 3.3 0.1 +70 50 Units V V C Table 2: Absolute Maximum Ratings Sym VDD RFin Vss Vin Tstrg Parameter Positive Supply Maximum RF Input RX1/RX2 Ground Logic I/P Voltage Storage Temp Min Max +3.6 +10 Units V dBm 0.0 -0.3 -40 0.1 VDD+0.3 +120 V V C Table 3: Electrical Characteristics Supply Current Idd (Supply Current) Sleep Receiving Transmitting Max 1µA 10mA 25mA Typ 500nA 7.5mA 25mA 50% Duty Cycle Table 4: Electrical Characteristics Digital Inputs Parameter Vih Vil Iih Iil 2 I C Internal Pullup Min 0.7*VDD Typ Max 0.3*VDD +1.0 -1.0 15 20 Units Volts Volts µA µA KΩ Table 5: Electrical Characteristics Digital Outputs Parameter Min Voh 0.8*VDD Vol Ioh Iol +1.0 2 I C Internal Pullup Typ AMI Semiconductor - Confidential www.amis.com Max 0.4 –1.0 15 Units Volts Volts mA mA 20 KΩ 2 Data Sheet AMIS-52000 Single-Chip Radio Transceiver Table 6: Electrical Characteristics Analog TX Parameter Frequency Range Modulation Min 260 Modulation Frequency 1.2 Max Output Power 5 Typ Max 433.92 700 ASK/OOK 6 On/Off Ratio VCO Gain, Kvco PLL Phase Noise Harmonics Reference Frequency Crystal Frequency Spurs TR Delay 8.125 Units MHz Comments Amplitude shift key on/off shift key 19.2 KBaud Approximate allowable data rates 7 dBm Over entire operating temperature and voltage range 60 75 -97 dB MHz/V dBc/Hz -97 dBc/Hz 100kHz offset, 50kHz loop bandwidth -35 dBc With typical matching circuits at 433.92MHz MHz dBc ms 10 PPM Xtal 13.56 -50 22.5 1 10kHz offset, 200kHz loop bandwidth 200kHz PLL loop bandwidth Transmit to receive delay Table 7: Electrical Characteristics Analog RX Parameter Frequency Range Modulation Min 260 Input Sensitivity RF Detect Time TR Delay -103 100 AMI Semiconductor - Confidential www.amis.com Typ 433.92 ASK/OOK Max 700 Units MHz Comments Amplitude shift key on/off shift key 1 dBm µs ms 10-3 BER, 1.2kbps Sniff Mode operation only Receiver to transmit delay 3 Data Sheet AMIS-52000 Single-Chip Radio Transceiver 5.0 Pin Definitions This section describes the pins of the AMIS-52000 package. Table 8: Pin List Pin # 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Name RX1 RX2 VCO2 VCO1 LPFILT RSSI/Bandgap Out NC CREF GND CLKOUT X1 X2 IIC Data NC IIC Clock TX/RX Data VDD RFPWR RFOUT RFGND Type RF RF Ana Ana Ana Ana Ana Ana Dig Ana Ana Dig Dig Dig Ana Ana RF Ana Comments RF Receive Antenna Input 1 RF Receive Antenna Input 2 Voltage Controlled oscillator 2 Voltage Controlled oscillator 1 Loop Filter Analog RSSI Output or Bandgap Output No connection Current Bias Precision Resistor Analog/Digital Ground RC or XTAL Output Xtal Input Xtal Output IIC Interface Data I/O No connection IIC Interface Clock Data Transmit or Data Receive Positive Power Supply Regulated Voltage Output for RF Transmitter Circuitry RF Transmit Antenna Output RF Ground Type Codes … Ana – Analog Dig – Digital RF – Radio Frequency 6.0 Package Outline Figure 1 – AMIS-52000 SSOP Package Dimensions Table 9: Package Dimensions Inches Dm A A1 A2 b D E E1 e Min 0.068 0.002 0.065 0.009 0.271 0.291 0.197 0.026 BSC AMI Semiconductor - Confidential www.amis.com Millimeters Max 0.078 0.20 0.073 0.015 0.295 0.323 0.221 Min 1.73 0.05 1.65 0.22 6.90 7.40 5.00 0.65 BSC Max 2.00 1.85 0.38 7.50 0.820 0.560 4 Data Sheet AMIS-52000 Single-Chip Radio Transceiver Data Sheet 7.0 Pin Descriptions RX1, RX2, RF Inputs The receiver uses an RSSI (Receive Signal Strength Indication) to recover the ASK/OOK (Amplitude Shift Keyed/On Off Shift Keyed) modulated data. RX1 and RX2 are RF antenna inputs to the AMIS-52000. The internal design of these circuits is identical. Each internal circuit can be trimmed to compensate for device process tolerances and external component tolerances. The first stage of the RF input is an LNA (Low Noise Amplifier). The receiver uses a low IF frequency and internal filters. The two inputs are “summed” before the data recovery circuit. The receiver is controlled by writing to the internal registers of the AMIS-52000: Table 10: Pin Descriptions Register Bit RX1 or RX2 Receiver Control (Registers 0x05, 0x0F and 0x17) Bit Name Bit State Comments 0 Register 0x05 1 3 Register 0x0F Register 0x17 & Register 0x05 53 Antenna #1 Enable Antenna #2 Enable RX Enable Continuous RX Register 0x17 Bit 6 & 7 Data Rate Cntl Register 0x05 Bit 2 BIT Order Bit 7 msb Bit 2 lsb 0 1 0 1 0 1 0 1 000 001 010 011 100 101 110 111 Receive circuits (RX1) are off Receive circuits (RX1) are controlled by Bit 3 Receive circuits (RX2) are off Receive circuits (RX2) are controlled by Bit 3 Receiver is disabled (off) Receiver is enabled (on) Normal operation RF receiver is turned on Set Data filter to 1.1kHz Set Data filter to 2.3kHz Set Data filter to 5.2kHz Set Data filter to 10.4kHz Set Data filter to 1.18kHz Set Data filter to 2.57kHz Set Data filter to 7.0kHz Set Data filter to 20.45kHz TX/RX, Data Input/Output The TX/RX pin (can be programmed to be the oscillator output) is the RC oscillator frequency. An external test system can use this signal in a feedback loop to trim the RC oscillator frequency. The TX/RX pin (in transmit operation) is the digital data input to the AMIS-52000’s transmit circuits. The data is used to turn the transmitter on or off. The AMIS-52000 does not perform protocol conversion to the data. It simply transmits when transmission is enabled. The state (low input or high input) that causes the AMIS-52000 to transmit is programmable. The TX/RX pin (during the Sniff or signal capture period) is an indicator (to a host controller) output that either the AMIS-52000 receiver has detected RF energy when the device is powered down with Sniff Mode enabled or the internal housekeeping timer has expired. When TX/RX is 2 used in this mode the I C data line will be high when RF energy is detected or low when the housekeeping timer activates the device. Depending on the bit period time, this acquisition could occur on the first bit of data and still receive the bit or it may require a pre-amble. The following timing chart shows the function of this pin in signal acquisition and Sniff Modes. The TX/RX pin (in receive) is the digital data output from the AMIS-52000 receiver. The received data is formed into high and low signals (ones and zeros) in a serial bit stream. The data output state (pin TX/RX) produced by the AMIS52000 receiver due to the presence of RF energy at the RX input can be programmed to be either a high level or a low level. An external controller must recreate the actual information. AMI Semiconductor - Confidential www.amis.com 5 AMIS-52000 Single-Chip Radio Transceiver Data Sheet A data bit or Period Figure 2: Receiver Data Acquisition Waveforms Figure 3: Receiver Acquisition Bit Function Timing Where: i is a delay allowing pins function to change to signal the HOST controller that a RF caused wakeup occurred. It can be controlled by Reg 0x0E (IRQ Delay). k (set by Reg 0x0B) is a delay allowing signal levels to settle before sampling RSSI. The TX/RX pin can be programmed to perform one of these functions by writing to the AMIS-52000 internal registers. Table 11: TX/RX Pin Definition Control (Registers 0x08, 0x0f and 0x17) Register 0x08 Bit 7 0x0F 2 0x17 5 0x17 5 0x0E All TX/RX Pin Definition Control (Registers 0x08, 0x0f, and 0x17) Bit Name Bit State Comments Sniff Out 0 Do not output Sniff on TX/RX pin 1 Output Sniff comparator results on TX/RX RC Osc. 0 TX/RX pin is normal operation (DATA) Out 1 RC osc. clock is output on the TX/RX pin TX/RX Inv 0 TX will output RF energy when TX/RX high Transmit 1 TX will output RF energy when TX/RX low TX/RX Inv 0 RX is a high level when RF energy is received Receive 1 RX is a low level when RF energy is received IRQ Delay Delay from TX/RX line signals a wakeup event to when the line returns to its normal function AMI Semiconductor - Confidential www.amis.com 6 AMIS-52000 Single-Chip Radio Transceiver Data Sheet VDD, Supply Voltage RFGND, RF Ground The VDD pin is the supply voltage for the AMIS-52000 circuits other than the RF output. It is typically 3.0V DC. Please refer to section “Operating and Maximum Specifications” of this specification for operating conditions. The RFGND pin is a ground connection for all the internal RF circuitry. X1, X2, Crystal Oscillator X1 and X2 connect a parallel resonance oscillator crystal and capacitors to the AMIS-52000. The AMIS-52000 is designed with an internal trim function that is controlled by writing to the AMIS-52000 registers. GND, Analog/Digital Ground The GND pin is a ground connection for all non-RF circuitry. Table 12: Crystal Divider Control Reg 0x03 Name TX Crystal Trim 0x04 RX Crystal Trim Register Function Changing the value of this changes the crystal frequency Changing the value of this changes the crystal frequency NOTE: The value of the external crystal load capacitors should be slightly lower than for a typical crystal to allow for capacitor loading in the trim function. LPFILT, Loop Filter Controlled Oscillator). The LC circuit tunes the VCO frequency. The frequency of the VCO is twice the desired TX or RX frequency and the range of the VCO is 520MHz to 1400MHz. The LPFILT pin connects the AMIS-52000 internal PLL comparator to the external loop filter. The filter is required to allow the internal PLL to lock to the crystal frequency while producing the desired RF frequency. A simple second order RC loop filter is typically sufficient for this purpose. CLKOUT, Internal Clock Output The CLKOUT pin output is either the internal RC oscillator, the crystal oscillator, or a divided version of the crystal oscillator. VCO1, VCO2, Voltage Controlled Oscillator Tune The VCO1 and VCO2 pins connect a parallel capacitor and inductor to the AMIS-52000 internal VCO (Voltage Table 13: Crystal Divider Control TX/RX Pin Definition Control (Registers 0x05 and 0x08) Register Register 0x05 Register 0x08 BIT 7 Register 0x0F 0&1 Bit Name CLKOUT Enable CLKOUT Output Select 4&5 CLKOUT Frequency Select Bit State 0 1 00 01 10 11 00 01 10 11 Comments CLKOUT is enabled CLKOUT is disabled Automatic control RC oscillator is output Xtal oscillator is output CLKOUT output is off Divide crystal by 4 Divide crystal by 3 Divide crystal by 2 Divide crystal by 1 CREF, Current Reference Bias handshaking and protocol is implemented for a SLAVE device. Because only a minimal configuration is supported, clock stretching for slow peripherals, general call addressing, and ten-bit extended addressing are not implemented. The interface will support either normal (0 100 Kbits/second) or fast (0 - 400 Kbits/second) data modes. The interface conforms to the Phillips specification 2 for the I C bus. The CREF pin requires a resistor to ground to set the bandgap BIAS CURRENT. IT IS CRITICAL THAT THE RESISTOR BE 33.2K OHMS, 1% or better tolerance. R(Bias) = 33.2 KΩ (1%) 2 2 2 I CDATA, I CCLK, I C Control Interface Bus 2 The AMIS-52000 implements an I C serial 8 bit bi-directional 2 2 2 interface with the pins I CDATA and I CCLK. The I C bus AMI Semiconductor - Confidential www.amis.com 7 AMIS-52000 Single-Chip Radio Transceiver Pin 2 I CDATA 2 I CCLK Device AMIS-52000 AMIS-52000 AMIS-52000 Function Resistor Units Internal Pullup Internal Pullup 15 15 K ohms K ohms Address 0110100X 01101000 01101001 Hex 68 69 Data Sheet Function Device address Device write Read device 2 The I2C pins are also used as part of the wake-up function of the AMIS-52000. When the AMIS-52000 is in power down 2 or sleep mode, the I CCLK line can be driven to a low state to wake the AMIS-52000. Then an external controller can interrogate the state of the I CDATA line to determine whether a Sniff function detected RF (data high) or a HOUSEKEEPING timer timeout (data low). RSSI/BG, Analog Output The RSSI/BG pin (when programmed to be) outputs the voltage of the internal Bandgap voltage reference. The RSSI/BG pin outputs the analog RSSI signal. This signal is filtered by an internal parallel connection of a resistor and capacitor to ground. Each of these functions for the RSSI/BG pin can be selected by writing to the AMIS-52000 registers. Table 14: RSSI/BG Analog Pin Definition Control (Registers 0x0F and 0x17) Register 0x0F Bit 3 Bit Name RSSI or Bandgap Output AMI Semiconductor - Confidential www.amis.com Bit State 0 1 Comments RSSI signal output (Pre Data Filter) Bandgap voltage is output 8 AMIS-52000 Single-Chip Radio Transceiver Data Sheet 8.0 Functional Design Description controlled by setting register TXPOWER (0x02) to some value, setting a DC voltage level on the pin RFPWR (0x00 is the lowest setting and 0xFF is the highest setting). The receive section of the AMIS-52000 is configured to accept the input signals from either or both of the two antennas. The detected signals are summed inside the receiver, providing the received digital signal output. The receiver operates as a very low IF superheterodyne receiver with internal filtering. The AMIS-52000 is a dual receiver and a transmitter in a single device. Data is transmitted at data rates up to 19.6Kbps. The AMIS-52000 can be used in half-duplex mode, or simplex mode. Control is provided by an external microprocessor. Power output adjust, frequency trim, filter bandwidth selection, antenna or receiver diversity selection and crystal divider values can be changed to compensate for device tolerances. The transmit section of the AMIS52000 generates the output carrier signal when the TX/RX pin is toggled to enable the RF carrier. RF output power is AMIS-52000 Block Diagram This section shows a typical design with external components for 433.92MHz operation. The following sections will describe each external circuit. Figure 4 - AMIS-52000 Reference Block Diagram RX1, RX2, RF Input Impedance There are two identical RF input circuits (AMIS-52000 pins RX1 and RX2). The LNA for these inputs requires a DC voltage path to ground. The following circuit diagram shows a suggested circuit for 433.92MHz. Figure 5 - 433.92MHz Typical Match to 50 Ohms AMI Semiconductor - Confidential www.amis.com 9 AMIS-52000 Single-Chip Radio Transceiver Data Sheet Table 15: RFIN Characteristics Specification Input Resistance Input Capacitance Input Resistance Input Capacitance Input Sensitivity Input Noise Figure Freq Range RF Input IP3 IP2 Settings RX trim 0x00 RX trim 0x00 RX trim 0xff RX trim 0xff Conditions Trim set minimum Trim set minimum Trim set maximum Trim set maximum Min Typ 2K 3 2K 6 -103 3 433 3 260 Max RF signal input Max 6 700 -10 +8 +66 Units Ω pF Ω pF dBm dB MHz dBm dBm dBm RFOUT, RF Output Impedance harmonics to acceptable levels. The following circuit is a suggestion for matching the output to 50Ω at 433.92MHz. The circuit includes a tuned parallel LC tank at the 433.92MHz (including internal capacitance) and an LC notch filter at the third harmonic. The RF transmitter output pin is RFOUT. This is an open drain output. It requires a DC signal path to RFPWR, which is the output of the internal power supply to the transmitter. The transmitter output requires a tuned resonant circuit externally to form the desired waveform. This resonant circuit should be resonant at the desired output frequency. The transmitter output also requires filtering to reduce the Figure 6 – 433.92MHz Typical Match to 50Ω Table 16: RFOUT Characteristics Specification Output Resistance Output Capacitance Output Resistance Output Capacitance Harmonics Freq Range Freq Range Modulation On/Off Ratio Output Power Output Power Settings TX PC 0x00 TX PC 0x00 TX PC 0xff TX PC 0xff TX PC 0xff Transmit Transmit Fast start crystal circuit TX PC 0x00 TX PC 0xff With typical match circuit With typical match circuit AMI Semiconductor - Confidential www.amis.com Conditions Min With typical match circuit 260 350 10 Typ 22 3 TBD TBD -35 433.92 433.92 ASK/OOK 60 -24 6 Max 700 480 Units Ω pF Ω pF dBc MHz MHz dB dBm dBm AMIS-52000 Single-Chip Radio Transceiver Data Sheet VCO1, VCO2, VCO Tuning supply voltage (Vloopfilter = (1/2) the VCC supply). Different combinations of the L and C should be tried until this secondary requirement is also met. The AMIS-52000 has an internal Voltage Controlled Oscillator (VCO). A parallel LC circuit (tuned to twice the desired RF frequency) is connected between the VCO1 and VCO2 pins to set the frequency of the VCO. This circuit is sensitive to the PCB board layout. The components should be located as close as possible to the AMIS-52000 part. There is a secondary requirement in the selection of the components for this function. When the component values meet the above resonant requirements, the loop filter voltage should be about in the mid range of the The parallel LC circuit tunes the internal VCO frequency. The frequency is determined by the following: Frequency = (2) * (Rxfreq) MHz ctot = CAP + 2.25 pF INDUCTOR = 1/((Ctot) * ((2πF)^2))) More detailed information on this function is found in the AMIS application note, “AMIS-52000 Extending the AMIS52000 Frequency Range Beyond the 433MHz Target.” Figure 6 – Frequency Tuning Components for 433.92MHz LPFFILT The AMIS-52000 uses a Phase Locked Loop to set the frequency stability of the oscillators. This circuit requires an external LOOP FILTER connected to pin LPF. The following second order loop filter is suggested. The components for this filter should be located as close to the AMIS-52000 part as possible in the PCB layout. More detailed information on the design of this filter is found in the AMIS application note, “AMIS-52000 Extending the AMIS-52000 Frequency Range Beyond the 433MHz Target.” Figure 7 – Typical Loop Filter Design AMI Semiconductor - Confidential www.amis.com 11 AMIS-52000 Single-Chip Radio Transceiver Data Sheet Table 17: PLL Design Parameters Items Ref Freq. ζ Fn Icp Kvco Description 433.93MHz external reference frequency Damping factor Natural frequency Charge pump current VCO sensitivity Min Typ 13.56 0.866 115 50 80 Max Units MHz kHz µA MHz/V CREF, Current Bias Resistor handshaking and protocol is implemented for a SLAVE device. The interface can connect directly to a host or 2 controller I C interface. There are internal pullup resistors 2 2 on both the I CDATA and I CCLK lines of the AMIS-52000. 2 The interface can handle data rates as defined in the I C specification up to 400Kbps. To insure proper operation of the AMIS-52000, this can only be a precision resistor with a value of 33.2KΩ. Use a 1% or better resistor tolerance. 2 2 I CDATA, I CCLK, Control Interface 2-wire Bus 2 The AMIS-52000 implements an I C serial 8 bit bi-directional 2 2 2 interface with the pins I CDATA and I CCLK. The I C bus Pin I2CDATA I2CCLK Function Internal pullup Internal pullup Resistor 15 15 Device AMIS-52000 AMIS-52000 AMIS-52000 Units KΩ KΩ Address 0110100X 01101000 01101001 Figure 8 – I2C Waveforms Showing Message START and STOP Conditions Figure 9 – I2C Waveforms Showing 8 BITs of Message and Acknowledge AMI Semiconductor - Confidential www.amis.com 12 Hex 68 69 Function Device address Device write Read device AMIS-52000 Single-Chip Radio Transceiver 2 Figure 10 – I C Waveforms Showing Write Message Format 2 Figure 11 – I C Waveforms Showing Read Message Format The protocol of the I2C bus is as follows: Clock is always from the MASTER Device Address is different for a WRITE (0x68) than for a READ (0x69) The SLAVE or MASTER when not outputting data leaves the data line high The SLAVE acknowledges each BYTE written to it The MASTER has the option of acknowledging the last READ BYTE of data Each message begins with a START and ends with a STOP Each message has DEVICE ADDRESS, REGISTER ADDRESS, and then DATA MASTER can write incrementing registers by just adding DATA BYTES to message When writing multi Data BYTES, add data to end of single DEVICE, REGISTER ADDRESS AMI Semiconductor - Confidential www.amis.com 13 Data Sheet AMIS-52000 Single-Chip Radio Transceiver Data Sheet X1, X2, Crystal Oscillator The AMIS-52000 requires a parallel resonant crystal. The frequency of this crystal can be in the frequency range of 12.5MHz to 14.5MHz. The AMIS-52000 will form an RF frequency for transmit and receive from this crystal frequency. The transmit frequency is 32 times the crystal frequency. The receive frequency is the same, but the AMIS52000 will pull the frequency to form an LO (local oscillator) frequency about 50kHz different than the signal frequency. A typical value for the 2 parallel load capacitors is 15pF. This may be less than the suggested values for a crystal due to the internal trim capacitance of the AMIS-52000. Figure 12 – Typical Crystal Oscillator Circuit function is explained in detail in AMIS application note, “AMIS-52000 Quick Start Crystal Oscillator Circuit Operation and Setup.” The AMIS-52000 contains a QUICK START function. For the frequencies that this circuit can operate (350 to 480MHz), the circuit can be used to stabilize the crystal frequency much faster than the normal crystal oscillator circuit. This Power-On-Reset/Brownout Detection The POR/Brownout Detection circuit ensures that the AMIS52000 will be in a reset state when VDD drops below certain threshold voltage, and remains in this state until VDD rises above another threshold voltage. The POR circuit characteristics are illustrated in Figure 13. Figure 13 – Power On Reset Characteristics AMI Semiconductor - Confidential www.amis.com 14 AMIS-52000 Single-Chip Radio Transceiver Data Sheet Sniff Signal Acquisition The AMIS-52000 is designed with a very low power mode. This mode shuts down the RF sections and CLKOUT circuitry. This mode has the RC oscillator and wake up divider circuits still running. To take full advantage of the low power state, the AMIS52000 has a Sniff Mode. In this mode, the AMIS-52000 will periodically wake the receiver to look for incoming RF energy. When the AMIS-52000 detects RF energy, it will 2 start the receive mode, while setting the I CDATA and 2 I CCLK lines to indicate to the host or controller that a wake up was generated by received signal. The minimum power use by the AMIS-52000 can be achieved by using the Sniff Mode to detect an incoming signal, while using the QUICK START function to start the crystal oscillator in a minimum time. Figure 14 - Sniff (Data Acquisition) Timing where: a: Delay (0x0B) before checking RSSI b: Time between Sniff functions (0x0A) c: Receiver on and sampling input signal Alternative Wake-Up The AMIS-52000 will wake from a low power mode upon the reception of RF energy. There is a second method for the AMIS-52000 to wake from its very low power mode. This low power mode is when the RF circuits and the CLKOUT circuits are shut off and the RC oscillator and wakeup divider chain are running. The AMIS-52000 can be programmed to wake up from time to time for housekeeping tasks. When the housekeeping timer occurs, 2 2 the AMIS-52000 will set the I CDATA and I CCLK lines to indicate to the host or controller that a housekeeping cycle is requested. AMI Semiconductor - Confidential www.amis.com © 2004 AMI Semiconductor, Inc. AMI Semiconductor makes no warranty for the use of its products, other than those expressly contained in the company’s standard warranty contained in AMI Semiconductor’s Terms and Conditions. The company assumes no responsibility for any errors which may appear in this document, reserves the right to change devices or specifications detailed herein at any time without notice, and does not make any commitment to update the information contained herein. No licenses to patents or other intellectual property of AMI Semiconductor are granted by the company in connection with the sale of AMI Semiconductor products, expressly or by implication.