BD3824FS-E2 - 2-Ch I2C Audio Signal Processor | ROHM | SSOP-32
Référence : BD3824FS-E2 ✓ ActifBD3824FS-E2 Présentation
An audio signal processor, also called a sound processor or audio I/O interface IC, is a mixed-signal block that sits between the analog line/tuner input stage and the system's digital-audio or DAC subsystem. Its job is to select the correct source, apply programmable gain and volume, and provide automatic level control so that recorded and played-back material keeps consistent loudness. In the broader hierarchy it belongs to signal-chain ICs -> audio processing -> audio amplifiers and special-purpose analog ICs.
The BD3824FS integrates a 5-channel input selector, input gain control, tuner gain control, automatic level control (ALC), a line amplifier, a 2-channel volume control circuit and a power-save ON/OFF function, all addressed over an I2C bus. Because every gain stage is digitally trimmable, a single board revision can serve multiple tuner and line-input routings without changing external passive networks. The datasheet also highlights low distortion and low noise as primary design targets for the audio path.
Because the I2C interface, ALC loop and volume block share one silicon die, the chip reduces external op-amps, switches and log/antilog networks. The BD3822FS sibling covers the level-meter and volume role, while BD3824FS covers the line-amplifier role; the two parts are pin compatible, so one board pattern supports both a high-end and a low-end model.
Typical uses include DVD recorder and DVD player analog audio boards, NTSC/PAL video deck audio front ends, set-top and video/audio combination decks, and other legacy consumer playback/record equipment that still relies on I2C-programmable analog level control.
When laying out the board, keep the I2C pull-ups short and route them away from the audio input traces; the ALC and gain stages amplify whatever noise couples in from the input pins. Also respect the single 9 V analog rail and decouple it locally, since supply ripple modulates the gain stages and the ALC detector.
This page brings together the distributor channel listings, the pin-compatible family relationship between BD3822FS and BD3824FS, and practical design notes on I2C control, ALC behaviour and analog layout that are not collected together in the manufacturer datasheet.
Alternatives de remplacement direct pour BD3824FS-E2 — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
BD3822FS
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
BD3824FS
✅ Remplacement direct ⚠️ Spécifications non vérifiées📋 Alternative de référence (hors catalogue)
BD3824FS-E2 Valeurs maximales et caractéristiques électriques
| Fonction | Audio signal processor / audio I/O interface |
| Channel Count | 2 channels |
| Tension d'alimentation | 9 V |
| Température de fonctionnement | -40 °C to +85 °C (TA) |
| Boîtier | SSOP-32 (32-SOP / PDSO32), 0.213 in / 5.40 mm body width |
| Lead Pitch | 0.8 mm |
| Nombre de broches | 32 pins |
| Process Technology | BICMOS |
| Control Interface | I2C bus |
| Integrated Blocks | 5-channel input selector, input gain, tuner gain, ALC, line amplifier, power save ON/OFF |
| Volume Control | 2-channel volume control circuit |
| Video Standard Support | NTSC / PAL |
| Primary Application | DVD recorder / DVD player analog audio I/O |
| Type de montage | Surface mount |
| Statut RoHS | Compliant |
Guide de configuration des broches du BD3824FS-E2 ssop-32 (32-sop / pdso32), 0.213 in / 5.40 mm body width
Configuration des broches du BD3824FS-E2 (boîtier ssop-32 (32-sop / pdso32), 0.213 in / 5.40 mm body width). Ce composant analogique comporte des broches d'entrée, de sortie et d'alimentation. Consultez la fiche technique du fabricant pour les configurations des broches d'annulation d'offset, de compensation et d'activation. Idéal pour le conditionnement de signaux et les circuits amplificateurs.
Aucune donnée de brochage détaillée disponible pour BD3824FS-E2.
Consultez la fiche technique pour la configuration complète des broches.
Applications typiques
BD3824FS-E2 convient pour 6 applications: DVD Recorder Analog Audio Front End, NTSC/PAL DVD Player Playback Board, Video Deck and Combination Audio Module, Tuner Audio Path with Automatic Level Control, Multi-Format Set-Top and Combo Analog Audio Board, Level-Meter and 2-Channel Volume Variant Board.
DVD Recorder Analog Audio Front End
The BD3824FS-E2 sits at the analog input stage of a DVD recorder main board, where analog line and tuner sources must be routed, level-matched and recorded at consistent loudness. Its 5-channel input selector, input gain and tuner gain blocks are all set over the I2C bus, so one firmware path can handle composite, component and tuner inputs without external switch matrices. The integrated ALC keeps recorded level stable across different source amplitudes, and the line amplifier provides the buffered path into the record chain. Running from a single 9 V rail at -40 °C to +85 °C ambient suits the consumer-availability requirements of DVD equipment, while the SSOP-32 footprint keeps the analog section compact enough for a multi-board chassis.
Recommandé
NTSC/PAL DVD Player Playback Board
In an NTSC/PAL DVD player the analog audio path must deliver clean playback from the decoder output, and the BD3824FS-E2 provides the line amplifier and programmable gain stage that sits between the decoder and the output amplifier. Its 2-channel volume control circuit lets the host processor set playback level over I2C, while the power-save ON/OFF function lets the player drop the analog path into a low-power state whenever the disc is stopped. Because the whole function set is digitally addressable, the same board can be reused for several player variants by changing firmware constants rather than the layout. The low-noise, low-distortion design targets of the die keep the playback path from adding audible artefacts to the recovered audio.
Recommandé
Video Deck and Combination Audio Module
Legacy video deck and A/V combination units use several analog sources, including tuner, composite and line inputs, that must be selected and level-controlled before recording or playback. The BD3824FS-E2 handles that with its 5-channel input selector plus separate input gain and tuner gain controls, all under I2C control from the deck's main microcontroller. Because the device is a sound processor rather than a general-purpose codec, it is best used as a dedicated analog audio block, paired with a separate stereo DAC such as the PCM1725DR for digital conversion. Its 32-pin SSOP-A32 package and single 9 V rail simplify the analog sub-board layout inside a mechanically constrained chassis.
Recommandé
Tuner Audio Path with Automatic Level Control
Broadcast and broadcast-adjacent tuner signals arrive at widely varying levels, so a tuner audio path benefits from the integrated ALC block of the BD3824FS-E2. The tuner gain control and ALC together keep the recorded or monitored level near a fixed target without a mechanical or analog-trim adjustment, and both are adjustable through the I2C interface so a single host controller can retune the behaviour per band or per region. The same die also provides the 5-channel input selector needed to bring the tuner source in alongside other analog inputs. Because ALC is a closed loop inside the chip, less analog area is needed on the board, though care is still needed to keep injected noise off the ALC detector input.
Recommandé
Multi-Format Set-Top and Combo Analog Audio Board
Set-top boxes and A/V combination decks that still carry legacy analog audio benefit from a single chip that centralises routing, gain, ALC and volume instead of a scattering of discrete op-amps and switch ICs. The BD3824FS-E2 gives the board one I2C-addressed audio brain that the system firmware can reconfigure as the source mix changes, and the power-save ON/OFF block allows the analog section to be shut down when the set is in standby, reducing standby current. Its 32-pin SSOP-A32 package and single-supply 9 V operation keep the analog sub-board small and straightforward to decouple. For designs with newer requirements, this is a legacy sound processor rather than a general-purpose codec, so verify feature overlap carefully.
Recommandé
Level-Meter and 2-Channel Volume Variant Board
The BD3822FS sibling of the BD3824FS-E2 provides the 1/2 power compression amplifier used for level metering together with the 2-channel volume block, and the two devices share a pin-compatible 32-pin SSOP footprint. That shared board pattern means the same analog audio PCB can be populated as a high-end model with the level-meter function or as a lower-cost model with the line amplifier fitted, letting a manufacturer cover two product tiers with one PCB and one firmware structure. The BD3824FS-E2 line-amplifier version is the better choice when the board needs to drive a line output directly from the selected analog input, while the compression-based level meter belongs to the metering branch. Both run from the same 9 V analog rail in the same footprint.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour BD3824FS-E2 — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | BD3822FS | BD3824FS |
|---|---|---|---|
| Brand | ROHM Semiconductor | ROHM Semiconductor | ROHM Semiconductor |
| Package | SSOP-32 (32-SOP / PDSO32) | SSOP-32 (32-SOP / PDSO32) - same footprint | SSOP-32 (32-SOP / PDSO32) - same footprint |
| Function | Audio signal processor with line amplifier | 1/2 power compression level-meter amplifier plus 2-channel volume | Audio signal processor with line amplifier (same die) |
| Channel Count | 2 channels | 2 channels | 2 channels |
| Control Interface | I2C bus | I2C bus | I2C bus |
| Integrated Blocks | 5-channel input selector, input gain, tuner gain, ALC, line amplifier, power save ON/OFF | 1/2 power compression amplifier for level meter, 2-channel volume | 5-channel input selector, input gain, tuner gain, ALC, line amplifier, power save ON/OFF |
Principaux différenciateurs
- Broader integrated function set in a single 32-pin SSOP (vs BD3822FS)
- Shared board pattern allows tiering without a new PCB (vs BD3822FS)
- Full I2C programmability of every analog block (vs Discrete op-amp front end)
Notes de conception
Route the I2C lines (SCL, SDA) and their pull-up resistors away from the analog input pins of the BD3824FS-E2. The input gain and ALC blocks amplify whatever is coupled into those nets, and a shared return path with the audio inputs is a common cause of hiss and of ALC pumping. Keep the analog ground and the digital I2C ground meeting at a single point close to the IC rather than at the board connector.
The BD3824FS-E2 runs from a single 9 V analog rail. Decouple that rail locally at the device with the value recommended in the manufacturer application circuit, and place the bulk capacitor near the board power entry point so that the ALC detector and gain stages see low impedance at audio frequencies. Supply ripple on this rail modulates the gain nodes directly and is amplified by the same blocks that set the recording level.
Do not treat the BD3824FS and BD3822FS as interchangeable without checking the block content. They are pin compatible and share the board pattern by design, but BD3822FS implements the 1/2 power compression level-meter amplifier plus 2-channel volume, while BD3824FS implements the line amplifier and the full input-selection and gain set. A firmware written for one part will not drive the other correctly even though the footprint and the I2C bus are the same.
Keep the analog input traces short and guard them from the clock and serial-data lines where possible. The tuner gain and ALC loops work best when the source impedance seen at the input pins stays low and stable, because ALC will otherwise react to noise instead of to program level. Place the input coupling capacitors close to the pins so that long PCB traces do not pick up interference before the gain stage.
Use the power-save ON/OFF function to shut the analog path down in standby rather than removing the 9 V rail. Dropping the supply forces a full re-settle of the ALC loop and the gain network on every wake, which produces audible level jumps on the first words of playback. Sequenced enable of the analog block ahead of the downstream DAC gives a cleaner, repeatable return to the correct level.
Informations de conformité
RoHS compliance is stated on the distributor product record for this ordering code. AEC-Q100 does not apply to this consumer legacy sound processor. Reach, lead-free, halogen-free and conflict-minerals status should be confirmed against the current manufacturer material declaration for the -E2 ordering code.
