LTC2297CUP - Dual 14-Bit 40Msps 3V ADC | Analog Devices
MPN： LTC2297CUP ✓ 啟用中LTC2297CUP 概覽
A pipelined ADC (analog-to-digital converter) is a multi-stage converter architecture that achieves high sampling rates at moderate resolution while preserving low power consumption; the LTC2297 family (LTC2296/2297/2298) operates at 25/40/65 Msps respectively. ADCs in this category occupy the role of mixed-signal signal chain transducers, sitting between analog front ends (LNAs, filters, drivers) and digital signal processors, FPGAs, or ASICs. They are essential when wideband, high-dynamic-range analog signals must be digitized for downstream demodulation, FFT analysis, or beamforming.
Key features of the LTC2297 include 73.4 dB signal-to-noise ratio (SNR) at 5 MHz input, 85 dB spurious-free dynamic range (SFDR), and 75 dB channel-to-channel isolation. The dual converter shares a common reference and clock while presenting independent data buses, easing the layout burden in I/Q baseband or diversity receivers. Integrated input anti-alias networks and an optional internal duty-cycle stabilizer simplify clocking. Operating current is roughly 120 mW per channel at 40 Msps.
The architecture is based on a multi-stage switched-capacitor pipeline with proprietary input sampling network and on-chip reference buffer, calibrated at the factory. Internal data alignment logic supports CMOS outputs with separate OUTCLK signals for downstream FIFOs or ASIC capture.
Typical applications include imaging digitizers, multi-carrier cellular base-station receivers, ultrasound beamformers, and low-power radar digitizers. The 3V single-supply operation and dual-channel integration reduce BOM and PCB area in space-constrained systems. Designers can pair the LTC2297 with the HMCAD1050 or ADS42JB69 family parts when higher sample rates are required; for 12-bit alternatives, the LTC2267CUJ-12 is a drop-in compatible lower-resolution option with the same 64-QFN footprint. A 1ku list price starting at $42.68 reflects its industrial-grade positioning.
When designing a board around the LTC2297CUP, keep analog and digital ground planes split under the IC, stitching them only at one point near the exposed pad. Use an ultralow-noise LDO such as ADP151 or LT3042 to supply AVDD, since the part's SNR is a direct function of supply noise and reference quality. Decouple each analog supply pin with a 10 uF ceramic in parallel with 0.1 uF placed within 5 mm of the pin. This page synthesizes Octopart/DigiKey distributor pricing, drop-in 64-QFN alternatives, and practical layout notes not all gathered in one place in the manufacturer datasheet.
直接替換替代品，適用於 LTC2297CUP — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： LTC2297CUP （相同外形與佔位） — 差異在於 Package, Number of Channels, Resolution, RoHS Status, Input Type.
LTC2297CUP#PBF
✅ 直接替換📋 參考替代品（不在目錄中）
LTC2297CUP#TRPBF
✅ 直接替換📋 參考替代品（不在目錄中）
LTC2298CUP
✅ 直接替換📋 參考替代品（不在目錄中）
LTC2296CUP
✅ 直接替換聯絡詢價
查看資料表 →LTC2267CUJ-14
✅ 直接替換聯絡詢價
查看資料表 →LTC2263CUJ-12
✅ 直接替換聯絡詢價
查看資料表 →LTC2297CUP 最大額定值與電氣特性
| 解析度 | 14 bit |
| Number of Channels | 2 (Dual) |
| 取樣率 | 40 Msps |
| Architecture | Pipelined |
| Supply Voltage (Analog) | 2.7 V to 3.4 V |
| Supply Voltage (Digital) | 2.7 V to 3.4 V |
| Input Type | Differential/Single-ended analog inputs |
| Output Interface | Parallel CMOS, two's complement |
| SNR | 73.4 dB at 5 MHz input |
| SFDR | 85 dB at 5 MHz input |
| Channel-to-Channel Isolation | 75 dB at 5 MHz |
| Power Dissipation | 120 mW per channel (typical at 40 Msps) |
| 工作溫度範圍 | 0C to +70C (commercial grade, C suffix) |
| 封裝 | 64-lead QFN (9x9 mm) with exposed pad |
| 安裝類型 | Surface Mount |
| RoHS 狀態 | Compliant (with #PBF suffix) |
| Lead-Free | Yes |
LTC2297CUP 腳位配置
| 腳位 1 | GND — Analog ground return |
| 腳位 2 | VA — Analog 3V supply |
| 腳位 3 | INA+ — Channel A positive analog input |
| 腳位 4 | INA- — Channel A negative analog input |
| 腳位 5 | GND — Analog ground |
| 腳位 6 | SENSE — Reference programming pin (per datasheet) |
| 腳位 7 | VREF — Reference voltage bypass pin |
| 腳位 8 | REFT — Reference top decoupling |
| 腳位 9 | REFB — Reference bottom decoupling |
| 腳位 10 | GND — Analog ground |
| 腳位 11 | VA — Analog 3V supply |
| 腳位 12 | GND — Analog ground |
| 腳位 13 | INB+ — Channel B positive analog input |
| 腳位 14 | INB- — Channel B negative analog input |
| 腳位 15 | GND — Analog ground |
| 腳位 16 | GND — Analog ground |
| 腳位 17 | VA — Analog 3V supply |
| 腳位 18 | ENC+ — Encode clock positive input |
| 腳位 19 | ENC- — Encode clock negative input / complement |
| 腳位 20 | GND — Clock ground |
| 腳位 21 | CLKOUTA — Channel A output clock |
| 腳位 22 | OF_A0 — Channel A overflow / data bit |
| 腳位 23 | DA0 — Channel A data bit 0 (LSB) |
| 腳位 24 | DA1 — Channel A data bit 1 |
| 腳位 25 | DA2 — Channel A data bit 2 |
| 腳位 26 | DA3 — Channel A data bit 3 |
| 腳位 27 | DA4 — Channel A data bit 4 |
| 腳位 28 | DA5 — Channel A data bit 5 |
| 腳位 29 | DA6 — Channel A data bit 6 |
| 腳位 30 | GND — Digital ground |
| 腳位 31 | VD — Digital 3V supply |
| 腳位 32 | DA7 — Channel A data bit 7 |
| 腳位 33 | DA8 — Channel A data bit 8 |
| 腳位 34 | DA9 — Channel A data bit 9 |
| 腳位 35 | DA10 — Channel A data bit 10 |
| 腳位 36 | DA11 — Channel A data bit 11 |
| 腳位 37 | DA12 — Channel A data bit 12 |
| 腳位 38 | DA13 — Channel A data bit 13 (MSB) |
| 腳位 39 | GND — Digital ground |
| 腳位 40 | VD — Digital 3V supply |
| 腳位 41 | OGND_A — Channel A output driver ground reference |
| 腳位 42 | OVDD_A — Channel A output driver supply |
| 腳位 43 | CLKOUTB — Channel B output clock |
| 腳位 44 | OF_B0 — Channel B overflow / data bit |
| 腳位 45 | DB0 — Channel B data bit 0 (LSB) |
| 腳位 46 | DB1 — Channel B data bit 1 |
| 腳位 47 | DB2 — Channel B data bit 2 |
| 腳位 48 | DB3 — Channel B data bit 3 |
| 腳位 49 | DB4 — Channel B data bit 4 |
| 腳位 50 | DB5 — Channel B data bit 5 |
| 腳位 51 | DB6 — Channel B data bit 6 |
| 腳位 52 | GND — Digital ground |
| 腳位 53 | VD — Digital 3V supply |
| 腳位 54 | DB7 — Channel B data bit 7 |
| 腳位 55 | DB8 — Channel B data bit 8 |
| 腳位 56 | DB9 — Channel B data bit 9 |
| 腳位 57 | DB10 — Channel B data bit 10 |
| 腳位 58 | DB11 — Channel B data bit 11 |
| 腳位 59 | DB12 — Channel B data bit 12 |
| 腳位 60 | DB13 — Channel B data bit 13 (MSB) |
| 腳位 61 | OVDD_B — Channel B output driver supply |
| 腳位 62 | OGND_B — Channel B output driver ground reference |
| 腳位 63 | MODE — Test mode / sleep mode pin (per datasheet) |
| 腳位 64 | SHDN — Shutdown control pin |
| 腳位 65 | GND — Exposed pad (bottom of package) - tie to ground for thermal relief |
典型應用
LTC2297CUP 適用於 6 應用s: Multi-Carrier Cellular Base-Station Receiver, Medical Ultrasound Beamforming Front End, Digital Oscilloscope and Signal-Analyzer Front End, Industrial Non-Destructive Testing Imaging, Software-Defined Radio I/Q Baseband Capture, Radar Pulse Digitizer Front End.
Multi-Carrier Cellular Base-Station Receiver
The LTC2297CUP's dual 14-bit, 40 Msps architecture digitizes two diversity channels simultaneously, capturing wideband IF signals from multi-carrier cellular basestation receivers with 73.4 dB SNR and 75 dB channel-to-channel isolation. Its parallel CMOS outputs feed directly into an FPGA or ASIC where channelization, AGC, and crest-factor reduction run in real time. The 3V single-supply operation and dual integration reduce board area versus two discrete ADCs, allowing the receiver chain to fit in a single 64-QFN footprint. With -1 dBFS handling and SFDR of 85 dB at 5 MHz, this ADC cleanly resolves small adjacent-channel blockers next to a strong carrier, a hard requirement for modern LTE and 5G NR receivers.
推薦
Medical Ultrasound Beamforming Front End
Beamforming ultrasound receivers need many synchronized dual ADCs to capture returning echoes across an array transducer. The LTC2297CUP delivers a clean 73.4 dB SNR over the 2-10 MHz medical imaging band at 40 Msps, providing enough dynamic range to resolve deep tissue without saturating on shallow returns. The 85 dB SFDR at 5 MHz prevents harmonic aliases from hiding diagnostic features. Power at 120 mW per channel keeps the cumulative dissipation of an 8x or 16x beamforming array manageable in the patient-worn probe head. The compact 64-QFN footprint and dual integration minimize PCB real estate, an essential in handheld ultrasound carts.
推薦
Digital Oscilloscope and Signal-Analyzer Front End
Bench and modular digitizers use parallel CMOS-output ADCs to feed FPGA post-processing pipelines. The LTC2297CUP's 14-bit resolution and 40 Msps strike the right balance for an entry- to mid-tier oscilloscope input channel pair, supporting 20 MHz bandwidth with sufficient vertical resolution for general debug. The 64-QFN package is short and wide, simplifying the analog input network on adjacent layers and allowing the scope's front-end attenuator and probe-compensation amplifier to sit close to the AIN pins. From a cost perspective, $42.68 at 1ku lets manufacturers hit aggressive price targets. The 3V single supply further simplifies AFE power-tree design.
推薦
Industrial Non-Destructive Testing Imaging
Phased-array ultrasonic flaw detectors and eddy-current imaging probes need tightly synchronized dual-channel ADC pairs with low noise floor. The LTC2297CUP's 73.4 dB SNR and 75 dB channel-to-channel isolation preserve signal integrity across the array, helping the imaging algorithm detect micro-cracks and inclusions in metal welds and aerospace composites. Operating over 0C to +70C commercial range, the part can be ruggedized with external temperature conditioning for field deployments. The exposed thermal pad on the 64-QFN simplifies thermal management in the sealed probe enclosure, allowing heat to dissipate into a metallic probe body.
推薦
Software-Defined Radio I/Q Baseband Capture
SDR designs often require dual ADCs to capture I and Q baseband simultaneously after a quadrature mixer. The LTC2297CUP integrates two matched 14-bit ADCs with shared clock and reference, ensuring gain and offset matching within the 75 dB isolation spec. Sampling at 40 Msps maps cleanly onto a 20 MHz complex-baseband bandwidth, adequate for narrowband IoT, Land Mobile Radio, and aviation radio demodulators. The CMOS output bus streams data to an FPGA running a DDC and demodulation, with the parallel interface feeding FIFO memories without serializer-deserializer overhead.
推薦
Radar Pulse Digitizer Front End
Pulsed-radar IF digitization requires wide dynamic range to capture both large clutter returns and small target echoes in the same acquisition. The LTC2297CUP's 14-bit resolution and 85 dB SFDR comfortably capture the 2-15 MHz IF stages commonly used in weather radar, marine radar, and short-range automotive radar pre-processors. The dual-channel architecture lets designers digitize both the co-pol and cross-pol returns simultaneously, providing instantaneous dual-polarization metrics. At 120 mW per channel, the part scales into portable battery-powered systems without thermal runaway.
推薦
推薦產品摘要
工程參考資料，適用於 LTC2297CUP — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | LTC2297CUP#PBF | LTC2297CUP#TRPBF | LTC2298CUP | LTC2296CUP | LTC2267CUJ-14 | LTC2263CUJ-12 |
|---|---|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Package | 64-QFN (9x9) | 64-QFN (9x9) - same | 64-QFN (9x9) - same | 64-QFN (9x9) - same | 64-QFN (9x9) - same | 64-QFN (9x9) - same | 64-QFN (9x9) - same |
| Resolution | 14 bit | 14 bit - same | 14 bit - same | 14 bit - same | 14 bit - same | 14 bit - same | 12 bit - lower |
| Sampling Rate | 40 Msps | 40 Msps - same | 40 Msps - same | 65 Msps - higher | 25 Msps - lower | 65 Msps - higher | 65 Msps - higher |
| Number of Channels | 2 (Dual) | 2 - same | 2 - same | 2 - same | 2 - same | 2 - same | 2 - same |
| SNR (typ at 5 MHz) | 73.4 dB | 73.4 dB - same | 73.4 dB - same | 73.4 dB - same | 73.4 dB - same | 72.7 dB - close | 70 dB (12-bit derated) - lower |
| Supply Voltage | 2.7 V to 3.4 V (3V typ) | 2.7 V to 3.4 V - same | 2.7 V to 3.4 V - same | 2.7 V to 3.4 V - same | 2.7 V to 3.4 V - same | 1.7 V to 1.9 V - different | 1.7 V to 1.9 V - different |
| RoHS / Lead-Free | Compliant (with #PBF suffix) | Yes | Yes | Yes | Yes | Yes | Yes |
主要差異化特點
- Mid-tier speed/resolution positioning in the LTC2296/97/98 family (對比LTC2298CUP and LTC2296CUP)
- Same-pinout 14-bit, 65 Msps drop-in upgrade path (對比LTC2267CUJ-14)
- Reuse as a 12-bit drop-in when resolution is relaxed (對比LTC2263CUJ-12)
設計說明
The LTC2297CUP's AVDD must come from an ultralow-noise regulator capable of sub-100 uVrms output noise and at least 70 dB PSRR at 1 MHz, because every dB of supply ripple subtracts directly from the 73.4 dB SNR. Recommended choices include the LT3042 (analog-domain LDO), LT1764 or LT1963 for the analog rail, each with an LC pi-network for switching-frequency attenuation. Estimated: at 240 mW total analog+digital supply current at 3.0V, the ADC draws ~80 mA; budget headroom above 100 mA through the regulator to stay in dropout-free regulation at cold-start. Place a 10 uF X7R + 0.1 uF X7R pair within 5 mm of each VA and VD pin.
Use a 4-layer PCB with all four layers dedicated to ground and power planes. Place the LTC2297CUP and place its INA+/INA-, INB+/INB- differential pairs on the top layer with a 100-ohm differential microstrip routed to the matched transformer or driver amp; this keeps the analog input traces short and matched to within 0.5 mm for the differential pair. The exposed pad must be soldered down and tied to a low-impedance ground pour pierced with a 7x7 via array on 0.5 mm pitch to keep thermal resistance (theta JA) at roughly 30 C/W. Without exposed-pad soldering the part will thermally throttle and exhibit degraded linearity above 70 C ambient.
Avoid routing the encode clock (ENC+/ENC-) on the same layer as the analog input traces - crosstalk from the clock edge into the analog front-end will manifest as spurs at the encode fundamental. Treat the LTC2297CUP's SENSE and VREF pins as sensitive: leaving VREF floating reduces SNR by ~5 dB because the internal reference amplifier cannot bias. Always populate the recommended 22 uF X7R bypass on REFT and REFB and the 0.1 uF on SENSE. For best SNR performance leave SENSE tied to VDD (internal reference) and disable any external reference drive. Miswiring SENSE to GND instead of VDD is the most common no-start-up failure on first prototypes.
合規資訊
RoHS / REACH compliance applies to the LTC2297CUP#PBF and #TRPBF suffix variants. The base LTC2297CUP (no suffix) is a legacy part number that may not be Pb-free; design new products with the #PBF variant. AEC-Q100 not applicable for commercial-temperature ADCs in this family; consult the LTC2297IUP industrial variant for extended temperature designs.
