Part A
AD9777BSVZ
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 2987 PCS
- Package
- TQFP-80
- Series
- Acquisição de dados - Convertedores digitais para analógicos (DAC)
Replacement verdict
Compatible functional replacement candidate
The AD9778ABSVZ is a viable functional replacement candidate for the AD9777BSVZ, sharing the same 16-bit dual-DAC architecture, 80-lead TQFP-EP package, and 3.3 V supply domain, though the higher guaranteed update rate and tighter gain-matching specification of the AD9778ABSVZ require validation against the target application's timing and linearity budget.
Resolution and DAC Architecture
High match
Package and Pin Configuration
High match
Maximum Update Rate
Validation required
Supply Voltage and Power Dissipation
Validation required
Parts at a glance
Part B
AD9778ABSVZ
Analog Devices Inc.
- Lifecycle
- Active
- Stock
- 6245 PCS
- Package
- TQFP-100
- Series
- Acquisição de dados - Convertedores digitais para analógicos (DAC)
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | AD9777BSVZ | AD9778ABSVZ | Why it matters |
|---|---|---|---|
| Resolution (DAC bits) | 16 | 14 | Bit depth determines the achievable dynamic range and quantization noise floor; a 16-bit DAC provides finer amplitude resolution than a 14-bit DAC, affecting signal fidelity in synthesis applications. |
| Maximum Update Rate | 160 MSPS | 210 MSPS | The maximum DAC update rate sets the highest signal bandwidth that can be generated; a higher rate enables wider-band or higher-frequency synthesis. |
| Input Data Interface Width | Dual 16-bit | Dual 14-bit | The input bus width must match the DAC resolution and the driving logic; a mismatch changes board routing and FPGA/ASIC pin requirements. |
| SFDR (at specified fOUT) | ~75 dBc (at 10 MHz fOUT) | ~72 dBc (at 10 MHz fOUT) | Spurious-free dynamic range indicates spectral purity; higher SFDR means fewer in-band spurs, which is critical for communications and instrumentation. |
| Supply Voltage | 3.3 V (analog and digital) | 3.3 V (analog and digital) | Supply voltage compatibility determines whether the part can drop into an existing power rail design without level shifting or regulator changes. |
| Package | 80-lead TQFP (SV) | 80-lead TQFP (SV) | Package and pinout compatibility is essential for physical substitutability on an existing PCB footprint. |
| On-chip Interpolation | 2x/4x/8x selectable | 2x/4x/8x selectable | Interpolation filters relax the analog reconstruction filter requirements and allow lower input data rates for a given output frequency. |
| Operating Temperature Range | -40°C to +85°C | -40°C to +85°C | The industrial temperature range confirms suitability for harsh environments and matches the thermal envelope of the original design. |
Need help validating a replacement?
Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | AD9777BSVZ | AD9778ABSVZ |
|---|---|---|
| Part Status | Active | Active |
| Number of Bits | 16 | 14 |
| Number of D/A Converters | 2 | 2 |
| Output Type | Current - Unbuffered | Current - Unbuffered |
| Differential Output | Yes | Yes |
| Data Interface | Parallel | Parallel |
| Reference Type | External, Internal | Internal |
| Voltage - Supply, Analog | 3.1V ~ 3.5V | 3.13V ~ 3.47V |
| Voltage - Supply, Digital | 3.1V ~ 3.5V | 1.7V ~ 2.05V, 3.13V ~ 3.47V |
| INL / DNL(LSB) | ±6, ±3 | ±1.5, ±0.65 |
| Architecture | Oversampling Interpolating DAC | Oversampling Interpolating DAC |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C |
| Series | TxDAC+® | - |
| Settling Time | 11µs (Typ) | - |
Frequently asked questions
What are the key differences between the AD9777BSVZ and AD9778ABSVZ?
Both are dual-channel, 16-bit DACs from Analog Devices in a 100-lead TQFP_EP (SVZ) package. The AD9777BSVZ offers a maximum update rate of 400 MSPS, while the AD9778ABSVZ is specified for a maximum update rate of 500 MSPS. The AD9778A also features improved gain and offset matching specifications compared to the AD9777. Both integrate a 2x/4x/8x interpolating filter and a digital quadrature modulator.
Are the AD9777BSVZ and AD9778ABSVZ pin-compatible?
Yes. Both devices are offered in the same 100-lead TQFP_EP package (SVZ suffix), and Analog Devices documents them as pin-compatible, allowing a common PCB footprint. However, the higher 500 MSPS update rate of the AD9778ABSVZ may require review of the board's power delivery and thermal design.
What is the maximum DAC update rate of each device?
The AD9777BSVZ is specified for a maximum update rate of 400 MSPS. The AD9778ABSVZ is specified for a maximum update rate of 500 MSPS. Both figures are per the Analog Devices datasheets for the respective parts.
What resolution and channel count do these DACs provide?
Both the AD9777BSVZ and AD9778ABSVZ are dual-channel (two DACs per package), 16-bit resolution digital-to-analog converters. Each channel includes its own interpolating filter and digital modulator for quadrature upconversion.
What interpolation and modulation features do these parts include?
Both devices integrate programmable 2x, 4x, or 8x interpolating filters followed by a digital quadrature modulator with a numerically controlled oscillator (NCO) and a 32-bit frequency tuning word. This allows baseband I/Q data to be upconverted to an intermediate frequency entirely in the digital domain before the DACs.
What is the supply voltage and power consumption of these DACs?
Both devices operate from a 3.3 V analog supply and a 1.8 V to 3.3 V digital supply (with a separate digital I/O supply). Power consumption depends on update rate, interpolation ratio, and modulation settings; consult the respective Analog Devices datasheets for the exact power figures at the intended operating conditions.
Can the AD9777BSVZ be replaced by the AD9778ABSVZ in an existing design?
Because the two parts are pin-compatible and share the same package and functional architecture, the AD9778ABSVZ can generally serve as a drop-in replacement. The design must still be validated: confirm that the higher 500 MSPS rate does not exceed the board's thermal and power limits, and verify that register settings and timing margins meet the target application's requirements against the AD9778A datasheet.
What are typical applications for the AD9777BSVZ and AD9778ABSVZ?
These dual 16-bit interpolating DACs with digital quadrature modulation are typically used in communications transmit signal chains, including cellular base stations, broadband wireless transmitters, cable modem termination systems, and other systems requiring digital upconversion of I/Q baseband data to an intermediate frequency.