Part A
AD9779ABSVZ
ADI公司
- Lifecycle
- Active
- Stock
- 2155 件
- Package
- TQFP-100
- Series
- 資料獲取-數模轉換器（DAC）
Replacement verdict
Not a drop-in replacement
The AD9779ABSVZ and AD9775BSVZRL are not drop-in replacements for one another. Although both are dual-channel high-speed DACs from Analog Devices in a 100-lead TQFP_EP package, they differ in resolution, maximum update rate, and digital input interface, so the AD9775BSVZRL cannot be substituted directly for the AD9779ABSVZ without redesign and revalidation.
Different resolution
Different sample rate
Different input interface
Validation required
Parts at a glance
Part B
AD9775BSVZRL
ADI公司
- Lifecycle
- Active
- Stock
- 2746 件
- Package
- TQFP-80
- Series
- 資料獲取-數模轉換器（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 | AD9779ABSVZ | AD9775BSVZRL | Why it matters |
|---|---|---|---|
| Resolution (DAC bits) | 16 | 14 | Higher resolution provides finer output quantization and lower quantization noise, affecting achievable SNR and signal fidelity. |
| Maximum Update Rate | 1000 MSPS | 400 MSPS | The maximum DAC update rate determines the highest synthesizable output frequency and the width of the usable Nyquist band. |
| Number of DAC Channels | 2 | 2 | Dual channels enable I/Q complex signal generation; matching channel count is essential for quadrature transmit architectures. |
| On-chip Digital Interpolation | 2x, 4x, 8x | 2x, 4x, 8x | Interpolation filters relax the input data rate requirements and simplify upstream digital signal processing. |
| Digital Interface | LVDS | LVDS | The input interface type must match the driving FPGA/ASIC to ensure reliable high-speed data transfer. |
| Supply Voltage (Analog/Digital) | 3.3 V / 1.8 V | 3.3 V / 3.3 V | Supply rail requirements affect board power design and level compatibility with surrounding logic. |
| Package | 100-lead TQFP (SVZ) | 80-lead TQFP (SVZ) | Package footprint and pin count determine PCB layout compatibility and whether a drop-in replacement is possible. |
| Power Consumption (typical) | ~1.0 W | ~0.7 W | Power dissipation impacts thermal design and overall system efficiency, especially in dense multi-channel systems. |
| SFDR (at rated update rate) | ~75 dBc | ~70 dBc | Spurious-free dynamic range indicates spectral purity and affects the ability to meet transmit mask requirements. |
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 | AD9779ABSVZ | AD9775BSVZRL |
|---|---|---|
| Supplier | - | Analog Devices Inc.,Rochester Electronics, LLC |
| Series | - | TxDAC+® |
| Part Status | Active | Active |
| Number of Bits | 16 | 14 |
| Number of D/A Converters | 2 | 2 |
| Settling Time | - | 11ns (Typ) |
| Output Type | Current - Unbuffered | Current - Unbuffered |
| Differential Output | Yes | Yes |
| Data Interface | Parallel | Parallel |
| Reference Type | Internal | External, Internal |
| Voltage - Supply, Analog | 3.13V ~ 3.47V | 3.1V ~ 3.5V |
| Voltage - Supply, Digital | 1.7V ~ 2.05V, 3.13V ~ 3.47V | 3.1V ~ 3.5V |
| INL / DNL(LSB) | ±6, ±2.1 | ±1.5, ±1 |
| Architecture | Oversampling Interpolating DAC | Oversampling Interpolating DAC |
| Operating Temperature | -40°C ~ 85°C | -40°C ~ 85°C |
Frequently asked questions
What are the key differences between the AD9779ABSVZ and AD9775BSVZRL?
The AD9779ABSVZ is a dual-channel, 16-bit, 1 GSPS digital-to-analog converter (DAC) with an integrated 2x/4x/8x interpolating filter and on-chip PLL. The AD9775BSVZRL is a dual-channel, 14-bit, 400 MSPS DAC with 2x/4x/8x interpolation. The AD9779A offers higher resolution (16-bit vs 14-bit) and a significantly higher maximum update rate (1 GSPS vs 400 MSPS), while both are housed in a 100-lead TQFP-EP package and operate from a 3.3 V analog supply with 1.8 V/3.3 V digital I/O options.
Are the AD9779ABSVZ and AD9775BSVZRL pin-compatible?
Both devices are offered in the same 100-lead TQFP-EP (SVZ) package, but pin compatibility must be verified against the respective datasheets before substitution. The AD9779A and AD9775 share a similar pinout architecture, but differences in supply pin assignments, clock input configurations, and control interface details mean a direct drop-in replacement should not be assumed without a detailed pin-by-pin comparison using the official Analog Devices datasheets.
What is the maximum DAC update rate for each device?
The AD9779ABSVZ supports a maximum DAC update rate of 1 GSPS (1000 MSPS). The AD9775BSVZRL supports a maximum DAC update rate of 400 MSPS. Designs requiring output frequencies or interpolation ratios beyond the AD9775's 400 MSPS limit must use the AD9779A or another higher-speed converter.
What resolution and channel count do these DACs provide?
Both are dual-channel DACs. The AD9779ABSVZ provides 16-bit resolution per channel, while the AD9775BSVZRL provides 14-bit resolution per channel. The higher 16-bit resolution of the AD9779A yields lower quantization noise and better dynamic range, which is relevant for wideband signal synthesis and communications applications.
Do both parts include an on-chip PLL and interpolating filters?
Yes. Both the AD9779ABSVZ and AD9775BSVZRL integrate selectable 2x/4x/8x digital interpolation filters and an on-chip clock multiplier PLL. These features allow the DAC to accept a lower-rate input data stream and internally interpolate to a higher DAC update rate, simplifying the external clocking and FPGA/ASIC interface requirements in both devices.
What are the supply voltage requirements for these DACs?
Both devices operate with a 3.3 V analog supply and support digital I/O supplies of 1.8 V or 3.3 V, allowing flexible interfacing to modern low-voltage logic. Designers should confirm exact supply rail tolerances and sequencing requirements in the respective Analog Devices datasheets, as the AD9779A and AD9775 may differ in detailed supply current and power dissipation specifications.
Which part should be selected for a wideband communications transmitter design?
For wideband transmit applications requiring higher resolution and higher output sample rates, the AD9779ABSVZ (16-bit, 1 GSPS) is generally the stronger choice because it supports wider instantaneous bandwidth and lower quantization noise. The AD9775BSVZRL (14-bit, 400 MSPS) is suitable for lower-bandwidth or lower-cost designs where 400 MSPS and 14-bit resolution meet the spectral mask and SNR requirements.