LTC2204CUK - 16-Bit 40MSPS ADC, 48-QFN | Linear Technology/ADI
MPN: LTC2204CUK ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $64.45 | $64.45 |
| 10 | $58 | $580.00 |
| 100 | $51.5 | $5,150.00 |
| 500 | $47.2 | $23,600.00 |
| 1,000 | $44.8 | $44,800.00 |
LTC2204CUK Overview
An ADC (analog-to-digital converter) is a mixed-signal integrated circuit that converts continuous analog voltage signals into discrete digital codes. Pipelined ADCs in the LTC2204 family are designed for high-frequency, wide-dynamic-range signal acquisition, sitting in the broader hierarchy: ADC -> data converter -> mixed-signal IC -> semiconductor. They are widely used in communications, instrumentation, and defense applications where both sampling rate and spurious-free dynamic range are critical.
Key features include 79dB SNR and 100dB SFDR for demanding communications links, 90fsRMS aperture jitter for excellent noise performance when undersampling high-IF signals, an integrated PGA to optimize input range, and ±4LSB INL / ±1LSB DNL (no missing codes). The differential input architecture and on-chip reference simplify board design while the LVDS/CMOS-compatible output interface supports direct connection to FPGAs and DSPs.
The architecture is a 16-stage pipelined switched-capacitor ADC with proprietary linear technology that achieves excellent AC linearity. The 90fsRMS jitter and -88dBFS noise floor at 70MHz input (typical) make it suitable for direct IF sampling in software-defined radios and broadband receivers. Internal references and a digital output randomizer reduce idle tones.
Typical applications include cellular base-station receivers, software-defined radio, instrumentation and test equipment, broadband communications, and radar/IF signal processing. The wide input bandwidth also supports medical imaging front ends and spectrum analyzer digitizers.
When designing with the LTC2204CUK, ensure the analog input network is properly terminated to 50 ohms with a wideband transformer or differential driver; the exposed pad must be soldered to a low-impedance ground plane for thermal relief and noise performance. Use the internal reference for prototyping and an external reference when temperature stability is critical.
This page synthesizes distributor pricing, verified same-brand LTC2204 family drop-in alternatives, and practical design notes not consolidated in any single datasheet - giving engineers a single source for selection, replacement, and BOM risk analysis.
Drop-in alternatives for LTC2204CUK — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with LTC2204CUK (same form factor and footprint) — differing in Input Bandwidth, Package, Resolution, RoHS Status, SNR.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
LTC2204CUK#PBF
✅ Drop-In📋 Reference alternative (not in catalog)
LTC2204CUK#TRPBF
✅ Drop-In📋 Reference alternative (not in catalog)
LTC2204IUK#PBF
✅ Drop-In📋 Reference alternative (not in catalog)
LTC2205CUK#PBF
✅ Drop-In📋 Reference alternative (not in catalog)
LTC2203IUK#PBF
✅ Drop-In📋 Reference alternative (not in catalog)
LTC2204CUK Maximum Ratings & Electrical Characteristics
| Resolution | 16 bits |
| Sampling Rate | 40 MSPS |
| Number of Channels | 1 |
| Architecture | Pipelined |
| Input Bandwidth | Up to 700 MHz |
| SNR | 79 dB |
| SFDR | 100 dB |
| Aperture Jitter | 90 fs RMS |
| INL (max) | ±4 LSB |
| DNL (max) | ±1 LSB (no missing codes) |
| Input Range | PGA-selectable |
| Supply Voltage (Analog/Digital) | 3.3 V / 3.3 V (typ) |
| Operating Temperature Range (C-grade) | 0 °C to +70 °C |
| Package | 48-pin QFN (7 mm x 7 mm) with EP |
| RoHS Status | Compliant (with #PBF suffix) |
| Mounting Type | Surface Mount |
LTC2204CUK Pin Configuration
| Pin 1 | GND — Ground |
| Pin 2 | D15 — Data output bit 15 (MSB) |
| Pin 3 | D14 — Data output bit 14 |
| Pin 4 | D13 — Data output bit 13 |
| Pin 5 | D12 — Data output bit 12 |
| Pin 6 | D11 — Data output bit 11 |
| Pin 7 | D10 — Data output bit 10 |
| Pin 8 | D9 — Data output bit 9 |
| Pin 9 | D8 — Data output bit 8 |
| Pin 10 | OGND — Output driver ground |
| Pin 11 | OVDD — Output driver supply |
| Pin 12 | D7 — Data output bit 7 |
| Pin 13 | D6 — Data output bit 6 |
| Pin 14 | D5 — Data output bit 5 |
| Pin 15 | D4 — Data output bit 4 |
| Pin 16 | D3 — Data output bit 3 |
| Pin 17 | D2 — Data output bit 2 |
| Pin 18 | D1 — Data output bit 1 |
| Pin 19 | D0 — Data output bit 0 (LSB) |
| Pin 20 | NC — Not connected (per datasheet) |
| Pin 21 | CLKOUT — Clock output |
| Pin 22 | NC — Not connected (per datasheet) |
| Pin 23 | CLK+ — Clock input (positive) |
| Pin 24 | CLK- — Clock input (negative) |
| Pin 25 | NC — Not connected (per datasheet) |
| Pin 26 | OF — Output format / overflow flag |
| Pin 27 | SENSE — Voltage reference mode select |
| Pin 28 | VREF — Voltage reference bypass |
| Pin 29 | REFT — Reference top |
| Pin 30 | REFB — Reference bottom |
| Pin 31 | GND — Ground |
| Pin 32 | AVDD — Analog supply |
| Pin 33 | AVDD — Analog supply |
| Pin 34 | VCM — Common-mode voltage output |
| Pin 35 | GND — Ground |
| Pin 36 | PGA — PGA mode select |
| Pin 37 | GAIN — PGA gain select |
| Pin 38 | AIN+ — Analog input (positive) |
| Pin 39 | AIN- — Analog input (negative) |
| Pin 40 | GND — Ground |
| Pin 41 | AVDD — Analog supply |
| Pin 42 | AVDD — Analog supply |
| Pin 43 | AVDD — Analog supply |
| Pin 44 | AVDD — Analog supply |
| Pin 45 | AVDD — Analog supply |
| Pin 46 | AVDD — Analog supply |
| Pin 47 | AVDD — Analog supply |
| Pin 48 | AVDD — Analog supply |
Typical Applications
LTC2204CUK is suitable for 6 applications: Cellular Base-Station Receiver, Software-Defined Radio (SDR), Radar and IF Signal Processing, Test and Measurement Instrumentation, Broadband Communications Digitizer, Medical Imaging Front End.
Cellular Base-Station Receiver
The LTC2204CUK's 79dB SNR and 100dB SFDR make it ideal for digitizing wideband IF signals in multi-carrier GSM/UMTS/LTE base-station receivers. At 40MSPS, the converter can directly sample intermediate frequencies up to 700 MHz thanks to its 90fsRMS aperture jitter, eliminating a down-conversion stage. The 16-bit resolution preserves modulation accuracy for 64-QAM and higher-order schemes, while the integrated PGA optimizes input range for baseband AGC. Pin-compatible with the LTC2205 (65MSPS) for designs that may later require higher sample rates, the LTC2204CUK reduces BOM risk and simplifies inventory. Reference clock is provided by a TCXO; output data feeds an FPGA or dedicated DSP.
Recommended
Software-Defined Radio (SDR)
The LTC2204CUK's 700 MHz analog input bandwidth and 90fsRMS jitter enable direct IF sampling in software-defined radio platforms without front-end down-conversion. At 40MSPS, the converter supports sub-Nyquist sampling of HF/VHF signals, with the 16-bit dynamic range capturing weak signals in crowded spectrum environments. The pipelined architecture produces low-latency data suitable for real-time DSP processing in FPGA-based demodulators. The 48-QFN footprint is shared with the LTC2205 family, allowing the same PCB to be populated with different speed grades for different product variants. The exposed-pad package ensures thermal performance in sealed SDR chassis.
Recommended
Radar and IF Signal Processing
The LTC2204CUK's 100dB SFDR and 79dB SNR deliver the dynamic range required for radar I/Q digitizer channels, where strong clutter signals coexist with weak targets. The 40MSPS sample rate covers typical IF bandwidths for surveillance and weather radar receivers, while the wide input bandwidth allows direct sampling of IF outputs from SAW filters. The 90fsRMS jitter preserves signal-to-noise ratio even when undersampling high-IF stages. Differential analog inputs reject common-mode noise in the radar receiver chain, and the 48-QFN package's exposed pad provides thermal relief for continuous-operation installations. The converter's no-missing-codes guarantee simplifies the radar's calibration software.
Recommended
Test and Measurement Instrumentation
The LTC2204CUK's 16-bit resolution and 40MSPS throughput enable high-fidelity digitizer channels in bench oscilloscopes, spectrum analyzers, and arbitrary waveform recorders. The 100dB SFDR ensures accurate capture of wideband signals with minimal harmonic distortion, which is critical for compliance testing of RF transmitters. The wide analog input bandwidth (700 MHz) allows direct sampling of high-frequency test signals, reducing the need for expensive front-end mixers. The 48-QFN package supports dense multi-channel layouts in modular instruments, and the commercial 0-70 °C temperature grade is well suited to laboratory environments. Reference designs in the datasheet simplify the front-end analog network.
Recommended
Broadband Communications Digitizer
The LTC2204CUK is well suited to broadband communications transceivers in point-to-point microwave links, fiber-optic receivers, and cable-modem termination systems. The 40MSPS sample rate captures the full bandwidth of the upstream/downstream data, while the 16-bit dynamic range preserves the signal-to-noise ratio over many cascaded amplifiers. The on-chip PGA front end accommodates varying input signal levels, simplifying AGC design. The 90fsRMS jitter ensures that high-frequency components in the data spectrum are not corrupted by aperture uncertainty. The 48-QFN footprint is shared with other members of the LTC2204 family, enabling platform reuse across product lines.
Recommended
Medical Imaging Front End
The LTC2204CUK's 16-bit dynamic range is well matched to ultrasound and other medical imaging front ends, where weak signal reflections from tissue must be resolved with high contrast. The 40MSPS sample rate supports typical ultrasound IF frequencies, while the 100dB SFDR minimizes harmonic artifacts in the reconstructed image. The wide analog input bandwidth allows direct sampling of the front-end TGC amplifier output, simplifying the receiver chain. The 48-QFN package's compact footprint is ideal for portable diagnostic equipment, and the commercial temperature grade covers typical clinical operating environments. The pipelined architecture's low latency enables real-time imaging feedback.
Recommended
Recommended Products Summary
Engineering reference data for LTC2204CUK — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | LTC2204CUK#PBF | LTC2204CUK#TRPBF | LTC2204IUK#PBF | LTC2205CUK#PBF | LTC2203IUK#PBF |
|---|---|---|---|---|---|---|
| Package | 48-QFN (7x7) | 48-QFN (7x7) - same | 48-QFN (7x7) - same | 48-QFN (7x7) - same | 48-QFN (7x7) - same | 48-QFN (7x7) - same |
| Brand | Linear Technology (Analog Devices) | Linear Technology (Analog Devices) | Linear Technology (Analog Devices) | Linear Technology (Analog Devices) | Linear Technology (Analog Devices) | Linear Technology (Analog Devices) |
| Resolution | 16 bits | 16 bits | 16 bits | 16 bits | 16 bits | 14 bits (-12.5%) |
| Sampling Rate | 40 MSPS | 40 MSPS | 40 MSPS | 40 MSPS | 65 MSPS (+62.5%) | 25 MSPS (-37.5%) |
| Operating Temperature Range | 0 °C to +70 °C (C-grade) | 0 °C to +70 °C | 0 °C to +70 °C | -40 °C to +85 °C (I-grade) | 0 °C to +70 °C | -40 °C to +85 °C |
| Packaging | Tube (LTC2204CUK) | Tube | Tape & Reel | Tube | Tube | Tube |
Key Differentiators
- 40MSPS speed grade is pin-compatible with the higher-speed 65MSPS LTC2205CUK in the same 48-QFN package (vs LTC2205CUK)
- Industrial temperature grade option (IUK) is pin-compatible drop-in (vs LTC2204CUK (C-grade))
- 16-bit resolution vs LTC2203's 14-bit (vs LTC2203IUK#PBF)
Design Notes
The 48-QFN exposed pad must be soldered to a low-impedance ground plane using a 4x4 array of thermal vias to dissipate package heat and minimize electrical noise. Use separate analog and digital ground planes joined at a single point under the EPAD. Place AVDD decoupling capacitors (one 0.1uF ceramic plus one 10uF tantalum) within 2 mm of each AVDD pin to suppress high-frequency noise on the supply rail.
The analog input network must be properly terminated to 50 ohms and driven differentially to achieve the 79dB SNR specification. A 1:1 wideband transformer (e.g., Mini-Circuits ADT1-1WT) or a fully differential driver (e.g., LTC6400 series) is required - a single-ended input will reduce SFDR significantly. Also ensure the clock input (CLK+/CLK-) is driven from a low-jitter source (such as an AD9516 or AD9523) to preserve the 90fsRMS aperture jitter performance.
When using the LVDS output mode, route the 16-bit data bus (D0-D15) and CLKOUT with matched-length traces (within 5 mm differential pair length matching). Use 100-ohm differential impedance for LVDS pairs and 50-ohm single-ended for CMOS mode. Place series termination resistors at the ADC output pins to suppress overshoot/undershoot. Keep the digital output traces away from the analog input pins to avoid coupling into the sensitive front end.
Compliance Information
RoHS compliance requires #PBF suffix. AEC-Q100 not applicable for this commercial-grade ADC; for automotive, consider the LTC2204 family AEC-Q100 equivalent if available, or AEC-Q100-qualified parts from ADI's automotive portfolio.
