The AD7715 is a complete analog front end for low frequency measurement applications. The part can accept low level input signals directly from a transducer and outputs a serial digital word. It employs a Σ-Δ conversion technique to realize up to 16 bits of no missing codes performance. The input signal is applied to a proprietary programmable gain front end based around an analog modulator. The modulator output is processed by an on-chip digital filter. The first notch of this digital filter can be programmed via the on-chip control register allowing adjustment of the filter cutoff and output update rate. The AD7715 consumes less than 450 μA in total supply current at 3 V supplies and 1 MHz master clock, making it ideal for use in low-power systems. Standby current is less than 10 μA. The programmable gain input allows the AD7715 to accept input signals directly from a strain gage or transducer removing a considerable amount of signal conditioning. The AD7715 is ideal for microcontroller or DSP processor applications with a three-wire serial interface reducing the number of interconnect lines and reducing the number of optocouplers required in isolated systems. The part contains on-chip registers which allow software control over output update rate, input gain, signal polarity, and calibration modes. The part features excellent static performance specifications with 16-bits no missing codes, ±0.0015% accuracy, and low rms noise (<550 nV). Endpoint errors and the effects of temperature drift are eliminated by on-chip calibration options, which remove zero-scale and full-scale errors.
The AD7715 features a differential analog input as well as a differential reference input. It operates from a single supply (3 V or 5 V). It can handle unipolar input signal ranges of 0 mV to 20 mV, 0 mV to 80 mV, 0 V to 1.25 V and 0 V to 2.5 V. It can also handle bipolar input signal ranges of ±20 mV, ±80 mV, ±1.25 V and ±2.5 V. These bipolar ranges are referenced to the negative input of the differential analog input. The AD7715 thus performs all signal conditioning and conversion for a single channel system.
The AD7715 is ideal for use in smart, microcontroller, or DSP-based systems. It features a serial interface that can be configured for three-wire operation. Gain settings, signal polarity, and update rate selection can be configured in software using the input serial port. The part contains self-calibration and system calibration options to eliminate gain and offset errors on the part itself or in the system.
CMOS construction ensures very low power dissipation, and power-down mode reduces the standby power consumption to 50 μW typical. The part is available in a 16-lead, 0.3 inch-wide, plastic dual-in-line package (PDIP) as well as a 16-lead 0.3 inch wide small outline (SOIC_W) package and a 16-lead TSSOP package.
Features and Benefits
| Analog to Digital Converters |
Document | note |
AD7715: 3V/5V, 450 µA, 16-Bit Sigma-Delta ADC Data Sheet (Rev. E) | PDF 474 kB |
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Part Number | Package | Packing Qty | Temp Range | Price 100-499 | Price 1000+ | RoHS |
---|---|---|---|---|---|---|
AD7715ACHIPS-3 Last Time Buy | CHIPS OR DIE | REEL 49 | -40 to 85C | 0 | 0 | Y |
AD7715ACHIPS-5 Last Time Buy | CHIPS OR DIE | REEL 49 | -40 to 85C | 0 | 8.48 | Y |
AD7715AN-5 Production | 16 ld PDIP | OTH 25 | -40 to 85C | 0 | 0 | N |
AD7715ANZ-3 Production | 16 ld PDIP | OTH 25 | -40 to 85C | 7.85 | 6.68 | Y |
AD7715ANZ-5 Production | 16 ld PDIP | OTH 25 | -40 to 85C | 7.85 | 6.68 | Y |
AD7715AR-3 Last Time Buy | 16 ld SOIC - Wide | OTH 47 | -40 to 85C | 0 | 0 | N |
AD7715AR-5 Production | 16 ld SOIC - Wide | OTH 47 | -40 to 85C | 7.78 | 6.6 | N |
AD7715AR-5REEL Production | 16 ld SOIC - Wide | REEL 1000 | -40 to 85C | 0 | 0 | N |
AD7715ARUZ-3 Production | 16 ld TSSOP | OTH 96 | -40 to 85C | 7.28 | 6.18 | Y |
AD7715ARUZ-3REEL7 Production | 16 ld TSSOP | REEL 1000 | -40 to 85C | 0 | 6.18 | Y |
AD7715ARUZ-5 Production | 16 ld TSSOP | OTH 96 | -40 to 85C | 6.93 | 5.89 | Y |
AD7715ARUZ-5REEL7 Production | 16 ld TSSOP | REEL 1000 | -40 to 85C | 0 | 5.89 | Y |
AD7715ARZ-3 Production | 16 ld SOIC - Wide | OTH 47 | -40 to 85C | 6.93 | 5.89 | Y |
AD7715ARZ-3REEL Production | 16 ld SOIC - Wide | REEL 1000 | -40 to 85C | 0 | 5.89 | Y |
AD7715ARZ-5 Production | 16 ld SOIC - Wide | OTH 47 | -40 to 85C | 6.93 | 5.89 | Y |
AD7715ARZ-5REEL Production | 16 ld SOIC - Wide | REEL 1000 | -40 to 85C | 0 | 5.89 | Y |