PCM1704U-J - 24-Bit 96kHz Sign-Magnitude DAC | Texas Instruments
MPN: PCM1704U-J ✗ Cuối đờiPCM1704U-J Tóm tắt
A sign-magnitude DAC is a digital-to-analog converter architecture that uses two complementary current sources switched in opposite phase per bit, rather than a thermometer-coded unary or segmented topology. This approach eliminates the major-carry switching glitches inherent in conventional binary-weighted DACs, yielding -40 dB lower glitch energy. In the broader hierarchy, the PCM1704U-J sits as an audio DAC, which is a sub-category of data-converter IC, itself under the mixed-signal IC umbrella in signal chain products. The BiCMOS process pairs bipolar precision transistors with CMOS logic, achieving fast settling of ±1.2 mA in 200 ns while drawing modest operating current.
The PCM1704U-J supports sampling frequencies from 16 kHz to 96 kHz with 8X oversampling when paired with a digital interpolation filter. Its fast current output of ±1.2 mA in 200 ns enables clean reproduction of transients in high-resolution audio material. Internal glitch-free differential current outputs eliminate mid-scale code-dependent distortion, while the on-chip precision bandgap reference stabilizes the output compliance over temperature.
Typical applications include high-end consumer CD/SACD players, professional studio digital mixers, audiophile outboard DACs, and mastering-grade A/D converters. The wide dynamic range also makes it useful in measurement instrumentation where 24-bit resolution at high update rates is required.
Key design considerations include using a true differential current-to-voltage converter (typically an op-amp such as the OPA1612 or OPA2134) and a low-noise voltage reference to bias the I-to-V stage. The 20-pin SOIC requires a standard SOIC-20 footprint, with analog and digital grounds tied at a single star point near the device.
This page synthesizes manufacturer datasheet specifications, current distributor pricing, drop-in same-family alternatives within TI's PCM1704 grading scheme, and practical application circuits that are not consolidated in the original datasheet.
Bộ thay thế dễ dàng lắp đặt cho PCM1704U-J — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với PCM1704U-J (cùng hình factor và footprint) — khác nhau ở Package, Resolution, Converter Type, Operating Temperature, Architecture.
PCM1704U-K/2K
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
PCM1704U
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PCM1704U-J/2K
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
PCM1704U-K
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PCM1704U/2K
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
PCM1704U-J Tỷ lệ tối đa & tính chất điện
| Converter Type | Sign-Magnitude Audio DAC |
| Độ phân giải | 24-bit |
| Sampling Frequency | 16 kHz to 96 kHz |
| Oversampling Support | 8X at 96 kHz (with external interpolation filter) |
| Dynamic Range | 112 dB typ (K grade); J grade lower |
| Signal-to-Noise Ratio (SNR) | 120 dB typ |
| THD+N (J Grade) | 0.0008% typ |
| Current Output | ±1.2 mA |
| Output Settling Time | 200 ns |
| Process Technology | BiCMOS |
| Input Data Format | Serial, 24-bit audio word |
| Hộp | 20-pin SOIC |
| Kiểu lắp đặt | Surface Mount |
| Nhiệt độ hoạt động | -25C to +85C |
Cấu hình chân PCM1704U-J
| Chân 1 | VCC — +5 V analog supply |
| Chân 2 | LRCK — Left/right word clock input |
| Chân 3 | DATA — Serial audio data input |
| Chân 4 | BCK — Bit clock input |
| Chân 5 | SYSCLK — System clock input |
| Chân 6 | GND — Digital ground |
| Chân 7 | VEE — Negative analog supply (-5 V) |
| Chân 8 | I_OUT+ — Positive current output |
| Chân 9 | I_OUT- — Negative (complementary) current output |
| Chân 10 | NC — Not connected per datasheet |
| Chân 11 | AGND — Analog ground |
| Chân 12 | VREF — Voltage reference (bias for I-to-V) |
| Chân 13 | NC — Not connected per datasheet |
| Chân 14 | NC — Not connected per datasheet |
| Chân 15 | NC — Not connected per datasheet |
| Chân 16 | NC — Not connected per datasheet |
| Chân 17 | NC — Not connected per datasheet |
| Chân 18 | NC — Not connected per datasheet |
| Chân 19 | NC — Not connected per datasheet |
| Chân 20 | NC — Not connected per datasheet |
Ứng dụng tiêu biểu
PCM1704U-J phù hợp cho 6 Áp dụngs: High-End CD/SACD Player, Professional Studio Digital Mixer, Audiophile Outboard DAC, Mastering-Grade A/D Converter, Broadcast Audio Equipment, Musical Instrument Digital Interface (MIDI) Synthesizer.
High-End CD/SACD Player
The PCM1704U-J fits audiophile CD/SACD player designs because its sign-magnitude topology eliminates mid-scale code-dependent glitches that binary-weighted DACs exhibit. With 120 dB SNR typical and 0.0008% THD+N at the J grade, the device delivers resolution and dynamic range sufficient for 24-bit/96 kHz source material. According to the manufacturer datasheet, it accepts 16 kHz to 96 kHz sampling with 8X oversampling when paired with an external interpolation filter such as the DF1704 or DIR9001. Pair the differential ±1.2 mA current outputs with a low-noise I-to-V converter (OPA1612 or OPA2134) and a star-grounded analog supply to preserve dynamic performance.
Được đề xuất
Professional Studio Digital Mixer
Studio digital mixing consoles benefit from the PCM1704U-J's 24-bit resolution at 96 kHz update rates, providing the low distortion headroom required for bus summing and monitor output stages. The 200 ns current-output settling handles transient-rich program material without slew-induced artifacts. Per the TI datasheet, the BiCMOS sign-magnitude architecture yields -40 dB lower glitch energy than conventional binary-weighted topologies, which is critical for preserving stereo imaging. Use a dual-supply (±15 V or ±12 V) rail for the I-to-V op-amp to maximize output swing in balanced professional line drivers.
Được đề xuất
Audiophile Outboard DAC
Standalone audiophile DACs leverage the PCM1704U-J's 120 dB SNR to deliver transparent playback of 24-bit high-resolution recordings. The differential current output topology inherently rejects common-mode power supply noise when driven from a low-noise regulator. The part operates over -25C to +85C per the manufacturer datasheet, suitable for consumer hi-fi equipment. Use a star-ground layout and separate analog/digital ground planes tied at one point near the device's GND pin to maximize dynamic performance. DAC designers often pair it with a tube or discrete output stage for harmonic character.
Được đề xuất
Mastering-Grade A/D Converter
In mastering audio interfaces, the PCM1704U-J serves as the monitor/reference DAC path, with its 120 dB SNR allowing direct comparison against the A/D conversion chain without adding audible coloration. Per the TI datasheet, its BiCMOS sign-magnitude topology provides THD+N of 0.0008% at J grade, low enough to be inaudible in critical listening. Pair with a high-precision master clock (e.g., crystal oscillator with <5 ppm jitter) and a low-jitter PLL such as the DIR9001 to extract the bit clock. AES3 balanced digital input is standard, with the I-to-V stage operating from a clean ±15 V supply.
Được đề xuất
Broadcast Audio Equipment
Broadcast audio routers and processors use the PCM1704U-J for monitoring output paths because its 120 dB SNR typical exceeds broadcast chain dynamic range requirements, leaving headroom for downstream mixers. Per the TI datasheet, the 24-bit/96 kHz capability supports modern AES3 and Dante broadcast formats. The ±1.2 mA differential current output stage rejects ground-loop noise common in broadcast facility wiring. Use isolation transformers (such as the PE-65612) on the output to comply with broadcast ground-isolation standards.
Được đề xuất
Musical Instrument Digital Interface (MIDI) Synthesizer
The PCM1704U-J fits high-end MIDI synthesizers and samplers where faithful playback of 24-bit sample libraries demands ultra-low distortion. The device's 16-96 kHz sampling range covers all standard pro-audio rates, and the BiCMOS sign-magnitude topology eliminates the mid-scale code transition glitches that introduce audible artifacts in fast envelope transients. Per the TI datasheet, the 200 ns settling time is well within budget for even the fastest 96 kHz update intervals. Combine with a low-jitter master clock and current-to-voltage conversion using a high-slew-rate op-amp.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho PCM1704U-J — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | PCM1704U-K/2K | PCM1704U | PCM1704U-J/2K | PCM1704U-K | PCM1704U/2K |
|---|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | 20-pin SOIC | 20-pin SOIC (same) | 20-pin SOIC (same) | 20-pin SOIC (same) | 20-pin SOIC (same) | 20-pin SOIC (same) |
| Performance Grade | J (mid) | K (highest) | U (base) | J (mid) - tape & reel | K (highest) - tray | U (base) - tape & reel |
| Dynamic Range (typ) | Mid (J grade) | 112 dB typ | Lower (U grade spec) | Mid (J grade) | 112 dB typ | Lower (U grade spec) |
| Resolution | 24-bit | 24-bit | 24-bit | 24-bit | 24-bit | 24-bit |
| Sampling Rate | 16-96 kHz | 16-96 kHz | 16-96 kHz | 16-96 kHz | 16-96 kHz | 16-96 kHz |
| Current Output | ±1.2 mA | ±1.2 mA | ±1.2 mA | ±1.2 mA | ±1.2 mA | ±1.2 mA |
| Packaging Format | Tube (J grade standard) | Tape & Reel | Tube | Tape & Reel | Tube/Tray | Tape & Reel |
| Lifecycle Status | Obsolete | Obsolete (K grade) | Obsolete | Obsolete (J grade) | Obsolete (K grade tray) | Obsolete |
Bảo phân biệt quan trọng
- Sign-magnitude topology eliminates mid-scale glitches (vsPCM1704U base grade)
- Pin-compatible upgrade to K grade available (vsPCM1704U-K/2K)
- Tape-and-reel option for high-volume assembly (vsPCM1704U-J/2K)
Ghi chú thiết kế
The PCM1704U-J requires clean +5 V analog (VCC) and -5 V (VEE) supplies plus a low-noise reference bias. Use a low-dropout regulator such as the TPS7A4701 (4.17 uVrms noise) or a linear pre-regulator. Add 10 uF + 0.1 uF ceramic decoupling close to the VCC and VEE pins to suppress switching noise from upstream digital supplies. Estimated: at ±5 V supplies with 1 mA quiescent draw, power consumption is approximately 10 mW.
Use a star-ground topology with separate analog and digital ground planes tied at a single point near the PCM1704U-J GND pin. Per the manufacturer datasheet, the differential current outputs are sensitive to common-mode ground loops; keep the I_OUT+ and I_OUT- traces equal-length and symmetric to the I-to-V op-amp inputs. Route the serial audio data lines (DATA, BCK, LRCK) away from the analog output traces to minimize digital feedthrough.
Drive the PCM1704U-J with a low-jitter master clock (jitter under 50 ps rms) for optimal 96 kHz dynamic range. Per TI, the SYSCLK input rejects amplitude noise but is sensitive to edge timing; use a dedicated crystal oscillator rather than a recovered PLL clock when possible. Decouple the I-to-V op-amp supply with a low-ESR electrolytic + ceramic to prevent supply-induced distortion.
Do not operate the PCM1704U-J without the VREF bias network or with floating unused inputs - per the datasheet, this can increase mid-scale distortion. The device is obsolete for new designs; consider PCM1794A or PCM1792 for long-term production, though these require PCB redesign. Avoid driving the I-to-V stage with a generic op-amp; use an audio-grade FET-input op-amp with low current noise.
Thông tin tuân thủ
Compliance status not provided in retrieved web data. RoHS, REACH, lead-free, and halogen-free status should be confirmed from the TI product folder before use in regulated markets.