LA1061

Ordering number : EN3044A Monolithic Linear IC LA1061M Antenna Switching Controller Overview The LA1061M is an antenna switching controller for mobile radio equipment. The LA1061M uses a number of inputs from the receiver circuitry to select the main antenna or sub-antenna according to signal strength and quality. Weak and strong signals are detected with the S-meter DC voltage and F.E. AGC voltage, respectively. Multi-path distortion is detected from the AC component of the IF output, using the same high-sensitivity counter circuit as in Sanyo's earlier LA1060 device. An auxiliary circuit keeps the main antenna selected for a fixed time period when reception conditions outside a moving vehicle are changing rapidly. The LA1061M is available in surface-mount 8-pin DIPs, facilitating construction of compact equipment. It operates from a single 7 to 12V power supply. Package Dimensions unit: mm 3111-MFP14S [LA1061M] SANYO: MFP14S Features • Uses Sanyo's proprietary AGC amplifier and detector, providing accurate detection of multi-path distortion. • High-current Main and Sub-antenna switching outputs. • Antenna switching frequency limiting circuit. • On-board comparators for F.E AGC (strong signal) and S-meter DC (weak signal) detection. • Surface-mount 14-pin MFP. Specifications Maximum Ratings at Ta=25°C Parameter Maximum supply voltage Allowable power dissipation Operating temperature Storage temperature Maximum flow-out current Symbol VCC max Pd max Topr Tstg I4 I5 I6 I9 I10 Maximum apply voltage I12 V13 V14 Pin 4 Pin 5 Pin 6 Pin 9 Pin 10 Pin 12 Pin 13 Pin 14 Conditions Ratings 14 182 –30 to +80 –40 to +125 1 10 10 2 5 2 VCC VCC Unit V mW °C °C mA mA mA mA mA mA V V SANYO Electric Co.,Ltd. Semiconductor Bussiness Headquarters TOKYO OFFICE Tokyo Bldg., 1-10, 1 Chome, Ueno, Taito-ku, TOKYO, 110 JAPAN 82997HA (KT)/9070TA/6019TA, TS No.3044-1/8 LA1061M Operating Conditions at Ta=25°C Parameter Recommended supply voltage Operating voltage range Symbol VCC VCC op Conditions Ratings 8 7 to 12 Unit V V Operation Characteristics at Ta=25°C, VCC=8V, f=100kHz sine wave Parameter Current drain Pin 5 ‘H’-level voltage Pin 6 ‘H’-level voltage Noise amp gain Noise detection sensitivity Noise count number Gate time 1 Pin 9 voltage Strong signal comparator threshold Weak signal comparator threshold Gate time 2 Gate time3 Switching frequency limit maximum count tG2 tG3 HCN 2 13 4 23 15 6 40 ms ms Vth13 1.8 2.0 2.2 V Symbol ICC V5 V6 Gv1 Gv2 NDS NCN tG1 V9 Vth14 Conditions No input, I5 and I6 are not included. 1kΩ to ground 1kΩ to ground VIN=3mVrms, f=100kHz VIN=100mVrms, f=100kHz Noise AGC off VIN=30mVrms, f=100kHz, sine wave Noise AGC off VIN=100mVrms, f=100kHz, R9=300kΩ 0.8 1.0 1.2 V 120 7.0 Ratings min 4.5 5.0 5.0 33 10 9 typ 7 6.0 6.0 36 13 12 10 150 7.7 180 8.0 µs V max 12 7.0 7.0 39 16 Unit mA V V dB dB 15 mVrms Equivalent Circuit Block Diagram Unit (resistance : Ω) No.3044-2/8 LA1061M Operating Characteristic Test Circuit Sample Application Circuit Unit (resistance : Ω, capacitance : F) Unit (resistance : Ω, capacitance : F) Sample Printed Circuit Pattern No.3044-3/8 LA1061M Functional Description General Operation The LA1061M has two inputs for weak and strong signal detection, and one for multi-path distortion detection. It has two outputs for Main and Sub-antenna selection, one of which is selected according to the state of the inputs. Both outputs can directly drive an antenna switching pin diode. Signal Strength Detection Each signal strength detection input has a built-in comparator. The weak signal comparator (pin 13) is driven by the S-meter DC voltage and has a threshold of approximately 2V. The antenna switching logic selects the Main antenna when the voltage on this pin is lower than the threshold, regardless of the state of the other inputs. The strong signal detector (pin 14) is driven by the F.E. AGC voltage and has a threshold of approximately 1V. The antenna switching logic selects the Sub-antenna if the voltage on this pin is lower than the threshold, the weak signal comparator is off, and the multi-path distortion detector is not already on. Multi-path Distortion Detection The IF output signal is high-pass filtered and the resulting noise signal input through a coupling capacitor to pin 1, the LA1061M amplifies this signal and applies AGC to it. The AGC amplifier is designed to detect multi-path distortion without amplifying noise due to a weak IF signal. The number of noise pulses within the period set by the time constant on pin 4 is counted. If it exceeds a certain limit, and the strong signal detector is not already on, the antenna switching logic selects the Main antenna. Switching Frequency Detection The LA1061M counts the number of antenna changes within the time interval set by the time constant on pin 12. The internal D/A converter outputs a current on pin 11, which is converted to a voltage by the resistor connected to this pin. If this voltage exceeds a certain value, that is, the switching frequency is too high, the Main antenna is selected for the period set by the time constant on pin 10. The Main antenna is selected for this time regardless of the state of the other inputs. Unit (resistance : Ω, capacitance : F) External circuits Isolate noise components present in the IF output signal with a high-pass filter, and input via a decoupling capacitor. Notes The input impedance of the LA 1061M varies with input level. The minimum value is 10kΩ. Pin Description Pin No. Function 1 Noise input Continued on next page. No.3044-4/8 LA1061M Continued from preceding page. Pin No. Function External circuits Unit (resistance : Ω, capacitance : F) Notes Highpass filter 2 H.P.F 3 AGC 4 Mono-stable multi-vibrator 1 Pin 6 is for MAIN, pin 5 is for SUB. 5 6 Antenna switching outputs 7 GND 8 VCC Continued on next page. No.3044-5/8 LA1061M Continued from preceding page. Pin No. Function External circuits Unit (resistance : Ω, capacitance : F) Notes 9 AGC Voltage output 10 Mono-stable multi-vibrator 3 11 D/A converter The LA1061M counts antenna switches for the time interval generated by multi-vibrator 2. The internal D/A converter outputs a current on pin 11, which is converted to a voltage by the resistor connected to this pin. If this voltage exceeds a certain value, that is, the switching frequency is too high , multi-vibrator 3 operates to hold the antenna switching outputs at Main for the time set by multi-vibrator 3. 12 Mono-stable multi-vibrator 2 The threshold level is set at approximately 2V. 13 Weak signal comparator The threshold level is set at approximately 1V. 14 Strong signal comparator No.3044-6/8 LA1061M Voltage gain, VG – dB Pin 1 Input voltage, VIN1 – dBµ Voltage gain, VG – dB Frequency, f – Hz Gate time, tG – µs Gate time, tG – µs Pin 4 capacity, C4 – nF Resistance, R – kΩ Weak Field Detection Level, hy – VCC Weak field detection level – V Pin 6 voltage, V6(H) – V Resistance,R6 – Ω Comparate Level, hy – Ta Switching frequency detection time – ms Supply Voltage, VCC – V Switching Frequency Detection Time – C12 Comparate level – V Hysteresis, hy – dB Ambient temperature, Ta – °C Pin 12 capacity, C12 – nF No.3044-7/8 Hysteresis, hy – dB LA1061M Switching Frequency Detection Time – R Switching frequency detection time – ms Antenna Hold Time – C10 Resistance, R – kΩ Antenna Hold Time – R Antenna hold time – s Pin 10 capacity, C10 – µF Antenna hold time – s Resistance, R – kΩ No products described or contained herein are intended for use in surgical implants, life-support systems, aerospace equipment, nuclear power control systems, vehicles, disaster/crime-prevention equipment and the like, the failure of which may directly or indirectly cause injury, death or property lose. Anyone purchasing any products described or contained herein for an above-mentioned use shall: Accept full responsibility and indemnify and defend SANYO ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors and all their officers and employees, jointly and severally, against any and all claims and litigation and all damages, cost and expenses associated with such use: Not impose any responsibilty for any fault or negligence which may be cited in any such claim or litigation on SANYO ELECTRIC CO., LTD., its affiliates, subsidiaries and distributors or any of their officers and employees jointly or severally. Information (including circuit diagrams and circuit parameters) herein is for example only; it is not guaranteed for volume production. SANYO believes information herein is accurate and reliable, but no guarantees are made or implied regarding its use or any infringements of intellectual property rights or other rights of third parties. This catalog provides information as of August, 1997. Specifications and information herein are subject to change without notice. No.3044-8/8