NTE3470 Integrated Circuit Floppy Disk Read Amplifier System Description: The NTE3470 is a monolithic READ Amplifier System for obtaining digital information from floppy disk storage. It is designed to accept the differential AC signal produced by the magnetic head and produce a digital output pulse that corresponds to each peak of the input signal. The gain stage amplifies the input waveform and applies it to an external filter network, enabling the active differentiator and time domain filter to produce the desired output. Features: D Combines All the Active Circuitry to Perform the Floppy Disk Read Amplifier Function in One Circuit D Improved (Positive) Gain TC and Tolerance D Improved Input Common Mode Absolute Maximum Ratings: (TA = +25°C, Note 1 unless otherwise specified) Power Supply Voltage (Pin11), VCC1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7V Power Supply Voltage (Pin18), VCC2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16V Input Voltage (Pin1 and Pin2), VI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.2 to +7.0V Output Voltage (Pin10), VO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.2 to +7.0V Operating Ambient Temperature Range, TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0° to +70°C Operating Junction Temperature, TJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +150°C Storage Temperature Range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –65° to +150°C Note 1. “Absolute Maximum Ratings” are those values beyond which the safety of the device cannot be guaranteed. They are not meant to imply that the device should be operated at these limits. The table of “Electrical Characteristics” provides conditions for actual device operation. Recommended Operating Conditions: Power Supply Voltage, VCC (VCC1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +4.75 to +5.25V (VCC2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +10 to +14V Operating Ambient Temperature Range, TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0° to +70°C Electrical Characteristics: (TA = 0° to +70°C, VCC1 = 4.75 to 5.25V, VCC2 = 10 to 14V unless otherwise specified) Parameter Differential Voltage Gain Input Base Current Input Common Mode Range, Linear Operation Symbol AVD Test Conditions f = 200kHz, ViD = 7mVRMS IIB Min Typ Max Unit 80 100 130 V/V – –10 –25 µA viCM 5% Max THD –0.1 – 1.5 V Differential Input Voltage, Linear Operation viD 5% Max THD – – 25 mVP–P Output Voltage Swing Differential voD 3 4 – VP–P Output Source Current, Toggled IO – 8.0 – mA Output Sink Current (Pin16 and Pin17) IOS 2.8 4.0 – mA 100 250 – kΩ Small Signal Input Resistance ri TA = +25°C Small Signal Output Resistance, Single Ended ro TA = +25°C, VCC1 = 5V, VCC2 = 12V – 15 – Ω viD = 2mVRMS, TA = +25°C, VCC1 = 5V, VCC2 = 12V 10 – – MHz TA = +25°C, f = 100kHz, AVD = 40dB, vin = 200mVP–P, VCC1 = 5V, VCC2 = 12V 50 – – dB VCC1 Supply Rejection Ratio TA = +25°C, VCC2 = 12V, 4.75V ≤ VCC1 ≤ 5.25V, AVD = 40dB 50 – – dB VCC2 Supply Rejection Ratio TA = +25°C, VCC1 = 5V, 10V ≤ VCC2 ≤ 14V, AVD = 40dB 50 – – dB Bandwidth, –3dB Common Mode Rejection Ratio BW CMRR Differential Output Offset VDO TA = +25°C, viD = vin = 0V – – 0.4 V Common Mode Output Offset VCO viD = vin = 0V, Differential and Common Mode – 3.0 – V Differential Noise Voltage Referred to Input en TA = +25°C, BW = 10Hz to 1MHz – 15 – µVRMS Supply Current ICC VCC1 = 5.25V, S1 to Pin12 or Pin13 – 40 – mA VCC2 = 14V – 4.8 – mA 1.0 1.4 – mA – – 5 % – 30 – kΩ – 40 – Ω Active Differentiator Section Differentiator Output Sink Current, Pin12 and Pin13 IOD VOD = VCC1 Peak Shift PS Note 2 Differentiator Input Resistance, Differential riD Differentiator Output Resistance, Differential roD TA = +25°C Note 2. f = 250kHz, viD = 1VP–P, icap = 500µA tPS1 – tPS2 x 100% tPS1 + tPS2 VCC1 = 5V, VCC2 = 12V where PS = 1/2 Electrical Characteristics (Cont’d): (TA = 0° to +70°C, VCC1 = 4.75 to 5.25V, VCC2 = 10 to 14V unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max Unit Digital Section Output Voltage High Logic Level, Pin10 VOH VCC1 = 4.75V, VCC2 = 12V, IOH = –0.4mA 2.7 – – V Output Voltage Low Logic Level, Pin10 VOL VCC1 = 4.75V, VCC2 = 12V, IOH = 8mA – – 0.5 V Output Rise Time, Pin10 tTLH – – 20 ns Output Fall Time, Pin10 tTHL – – 25 ns t1A, t1B 500 – 4000 ns 85 – 115 % 150 – 1000 ns 85 – 115 % Timing Range Mono #1 (t1A and t1B) Timing Accuracy Mono #1 Et1 Timing Range Mono #2 t2 Timing Accuracy Mono #2 Et2 t1 = 1µs = 0.625 R1C1 + 200ns, Note 3, Note 4, Note 5 t2 = 200ns = 0.625 R2C2, Note 6, Note 7 Note 3. R1 = 6.4kΩ, C1 = 200pF. Note 4. Accuracy guaranteed for R1 in the range 1.5kΩ ≤ R1 ≤ 10kΩ and C1 in the range 150pF ≤ C1 ≤ 680pF. Note 5. To minimize current transients, C1 should be kept as small as is convenient. Note 6. R2 = 1.6kΩ, C2 = 200pF. Note 7. Accuracy guaranteed for R2 in the range 1.5kΩ ≤ R2 ≤ 10kΩ and C2 in the range 100pF ≤ C1 ≤ 800pF. Pin Connection Diagram Amplifier Input 1 18 VCC2 Amplifier Input 2 Offset Decoupling 3 17 Amplifier Output 16 Amplifier Output Offset Decoupling 4 15 Active Differentiator Input GND 5 14 Active Differentiator Input One–Shot Component Mono #1 6 One–Shot Component Mono #1 7 One–Shot Component Mono #2 8 13 Differentiator Component 12 Differentiator Component 11 VCC1 One–Shot Component Mono #2 9 10 Data Output 18 10 .250 (6.35) 1 9 .870 (22.0) Max .325 (8.25) .160 (4.06) Max .100 (2.54) Typ .800 (20.32) .125 (3.17) Min