LTC1402 Linear Technology, LTC1402 Datasheet
LTC1402
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LTC1402 Summary of contents
Page 1
... SFDR at the Nyquist input frequency of 1.1MHz with dual 5V supplies and –84dB SFDR with a single 5V supply. The LTC1402 has two power saving modes: Nap and Sleep. Nap mode consumes only 15mW of power and Sleep can wake up and convert immediately. In Sleep mode, it typically consumes power. Upon power- ...
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... SS Digital Output Voltage ......... (V – 0.3V Power Dissipation .............................................. 250mW Operation Temperature Range LTC1402C ............................................... LTC1402I ............................................ – Storage Temperature Range ................. – 150 C Lead Temperature (Soldering, 10 sec).................. 300 C U CONVERTER CHARACTERISTICS temperature range, otherwise specifications are at T PARAMETER Resolution (No Missing Codes) ...
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... A DD OUT V = 4.75V 1.6mA DD OUT OUT 0V OUT 0V OUT OUT DD LTC1402 MIN TYP MAX 72.5 69 72.0 –89 –89 –74.5 –87 –82 –93 –84 –84 –84 0.18 82 5.0 3.5 denotes the specifications which apply over the MIN TYP MAX 4.096 15 1 ...
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... LTC1402 W U POWER REQUIRE E TS range, otherwise specifications are SYMBOL PARAMETER V Positive Supply Voltage DD V Negative Supply Voltage SS I Positive Supply Current DD I Negative Supply Current SS PD Power Dissipation CHARACTERISTICS range, otherwise specifications are SYMBOL PARAMETER f Maximum Sampling Frequency (Conversion Rate) ...
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... INPUT FREQUENCY (Hz) LTC1402 sequence. The OUT has stopped slewing in REF . REF input sine wave. P-P (Bipolar Mode Plots Run with Dual 5V Supplies for Unipolar SNR vs Input Frequency (Bipolar) – ...
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... LTC1402 W U TYPICAL PERFOR A CE CHARACTERISTICS Unipolar Mode Plots Run with a Single 5V Supply. V Sine Wave Spectrum Plot (Bipolar) 5V Supply 2222222.22Hz SAMPLE 109592.01Hz SINE –10 2048 SAMPLES –20 –30 –40 –50 –60 4TH –70 2ND 5TH –80 3RD 6TH –90 – ...
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... F ceramic ( tantalum in parallel with 0.1 F ceramic). AGND1 (Pin 2): Analog Ground. Tie to solid analog ground plane. The analog ground plane should be solid and have no cuts near the LTC1402 (Pin 3): Positive Analog Signal Input 4.096V in IN unipolar mode and 2 ...
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... LTC1402 PIN FUNCTIONS GAIN (Pin 7): Tie to AGND2 to set the reference voltage to 4.096V or tie set the reference voltage to 2.048V. REF (Note 4) BIP/UNI (Pin 8): Tie to logic low to set the input range to unipolar mode or tie to logic high to set the input range to bipolar mode. (Note 4) OGND (Pin 9): Output Ground for the Output Driver ...
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... REFRDY BIT + 12-BIT DATA WORD t CONV t THROUGHPUT Nap Mode and Sleep Mode Waveforms t 1 SCK to D Delay OUT SCK OUT V OL LTC1402 ACQ SAMPLE WORD ...
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... IN increasing the time between conversions. The best choice for an op amp to drive the LTC1402 will depend on the application. Generally, applications fall into two catego- ries: AC applications where dynamic specifications are most critical, and time domain applications where DC accuracy and settling time are most critical. The following list is a summary of the op amps that are suitable for driving the LTC1402 ...
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... Figure 3. 1MHz Fifth Order Elliptic Lowpass Filter BIPOLAR AND UNIPOLAR INPUT RANGES The 2V bipolar input range of the LTC1402 is optimized for low noise and low distortion. Most op amps also perform best over this same range, allowing direct cou- pling to the analog inputs and eliminating the need for special translation circuitry ...
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... U ADC can then be adjusted to match the peak input signal, maximizing the signal-to-noise ratio. The filtering of the internal LTC1402 reference amplifier will limit the band- width and settling time of this circuit. A settling time of 5ms should be allowed after a reference adjustment. DIFFERENTIAL INPUTS The LTC1402 has a unique differential sample-and-hold circuit that allows inputs from – ...
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... FREQUENCY (MHz) Figure 7. CMRR vs Input Frequency FULL-SCALE AND OFFSET ADJUSTMENT Figure 8 shows the ideal input/output characteristics for the LTC1402 in bipolar mode and unipolar mode. Figure 9a shows the components required for full-scale error ad- justment. Figure 9b includes the components for offset and full-scale adjustment. ...
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... POWER-DOWN MODES bypass capacitor and Upon power-up, the LTC1402 is initialized to the active state and is ready for conversion. The Nap and Sleep Mode waveforms show the power-down modes for the LTC1402. LTC1402 AGND2 ...
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... A simple approach to generate CONV is to create a pulse that is one SCK wide to drive the LTC1402 and then buffer this signal with the appropriate number of inverters to drive the frame sync input of the processor serial port good practice ...
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... DSP port, this signal will have the same jitter of the DSP’s master clock. SERIAL TO PARALLEL CONVERSION You can take advantage of the serial interface of the LTC1402 in a parallel data system to minimize bus wiring conges- tion in the PC board layout. Figure 12 shows an example of this interface ...
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... SCK 10 D OUT 9 OGND ; *************************************************************************** ; Files: BSP2KB.ASM -> ; 2kbyte collection into DSKPlus TMS320C542 with Serial Port interface to LTC1402 ; first element at 1024, last element at 1023, two middle elements at 2047 and 0000 ; bipolar mode ; *************************************************************************** .width 160 .length 110 .title “sineb0 BSP in auto buffer mode” ...
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... LTC1402 U U APPLICATIONS INFORMATION ; ————————Buffered Receive Interrupt Routine ————————— breceive: ifr = #10h ; clear interrupt flags TC = bitf(@BSPCE,#4000h) ; check which half (bspce(bit14)) of buffer if (NTC) goto bufull ...
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... DO NOT MODIFY IF USING DEBUGGER * nop nop .space 52*16 ;0C-3F: vectors for software interrupts 18-30 int0 return_enable ;40; external interrupt int0 nop nop nop int1 return_enable ;44; external interrupt int1 nop nop nop int2 return_enable ;48; external interrupt int2 nop nop nop W U LTC1402 19 ...
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... LTC1402 U U APPLICATIONS INFORMATION tint return_enable ;4C; internal timer interrupt nop nop nop brint goto breceive ;50; BSP receive interrupt nop nop nop bxint goto bsend ;54; BSP transmit interrupt nop nop nop trint return_enable ;58; TDM receive interrupt nop nop nop PACKAGE DESCRIPTION 0.015 0.004 (0.38 0.10) 0.007 – ...