MC44BS373CAD - PLL-Tuned UHF/VHF Audio/Video Modulator | NXP
MPN: MC44BS373CAD ⚠ Lần mua cuốiMC44BS373CAD Tóm tắt
A modulator (in this context, an RF modulator) is a transmitter IC that mixes a baseband audio and composite-video signal up to a UHF or VHF carrier suitable for direct injection into the antenna input of an analog television receiver. RF modulators sit between the source device (VCR, set-top box, DVD player) and the TV, and historically they were implemented as discrete mixer/oscillator chains. The MC44BS373CA family replaced that discrete chain with a fully integrated PLL-synthesized modulator, dropping dozens of components into a single 16-pin SOIC. Within the broader taxonomy, this part is an RF IC -> modulator -> consumer video IC -> semiconductor.
Key specifications include a typical TV output level of 82 dBuV at the antenna terminal, I2C control at standard-mode 100 kHz or fast-mode 400 kHz, multi-standard support (B/G, D/K, M/N, L), and a single 5 V supply. The PLL is fully programmable via the serial interface, removing the manual channel-adjustment trimmers that legacy designs required. A bypass mode supports test and modulation-disabled conditions for factory alignment.
Architecturally, the MC44BS373CA uses an on-chip PLL frequency synthesizer driven by an external reference resonator, a programmable divider, and a double-balanced mixer that combines the modulated audio subcarrier with the composite video baseband. The result is a low-phase-noise carrier that meets ETSI EN 50083-13 and FCC Part 15 emission masks for consumer TV modulator products. Compared with the legacy MC44BS373/4 family, the MC44BS373CA revision lowers power consumption and provides finer carrier frequency step resolution.
Typical applications include VCR RF output stages, satellite and terrestrial set-top box modulators, DVD player composite-to-RF conversion, game consoles, and CCTV/security observation systems that need to feed analog TV monitors. The wide standard coverage allows a single BOM to ship into multiple regional markets, simplifying manufacturing.
Designers should note that the part requires a 75 ohm output network and proper shielding to meet conducted and radiated emissions limits. The external reference resonator value determines the carrier frequency step, and any drift in this component directly translates into channel offset on the TV.
This page synthesizes distributor pricing, drop-in alternatives, application circuits, and practical design notes not found in the standalone datasheet.
Bộ thay thế dễ dàng lắp đặt cho MC44BS373CAD — 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 MC44BS373CAD (cùng hình factor và footprint) — khác nhau ở Package, Mounting Type, TV Output Level, Audio Subcarrier, Manufacturer.
MC44CC373
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MC44CC374
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MC44BS374CAEF
✅ Drop-In ⚠️ Thông số chưa được xác minh📋 Tham chiếu thay thế (không có trong danh mục)
MC44BS373CAFC
✅ Drop-In ⚠️ Thông số chưa được xác minhLiên hệ để biết giá
Xem tài liệu →MC44BS373CAEF
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MC44BS373CAD Thông số kỹ thuật
| Device Type | PLL-Tuned UHF/VHF Audio/Video Modulator |
| Chức năng | NTSC/PAL Modulator |
| Modulation Standard | NTSC, PAL (B/G, D/K, M/N, L) |
| Điện áp cung cấp | 5 V typical |
| Control Interface | I2C, 5 V and 3.3 V compatible |
| Output Frequency Range | UHF and VHF bands |
| TV Output Level | 82 dBuV typical |
| RF Output Structure | Double-balanced mixer + on-chip PLL |
| Audio Subcarrier | Programmable via I2C |
| Hộp | 16-SOIC (SO16NB, 0.154 inch / 3.90 mm width) |
| Kiểu lắp đặt | Surface Mount (gull-wing) |
| Khoảng nhiệt độ hoạt động | 0 C to +85 C |
| Lead-Free / RoHS | Lead-Free version available (MC44BS373CAEF,R2) |
| Standards Compliance | ETSI EN 50083-13, FCC Part 15 (typical consumer-TV emission masks) |
Cấu hình chân MC44BS373CAD
| Chân 1 | CVBS — Composite video baseband input |
| Chân 2 | AUDIO — Audio baseband input |
| Chân 3 | SCL — I2C serial clock |
| Chân 4 | SDA — I2C serial data |
| Chân 5 | ADDR — I2C address select |
| Chân 6 | PLL_LF — PLL loop filter |
| Chân 7 | XTAL1 — Reference resonator / oscillator input |
| Chân 8 | XTAL2 — Reference resonator output |
| Chân 9 | GND — Ground |
| Chân 10 | RFOUT — RF output to antenna network |
| Chân 11 | VDD — +5 V supply |
| Chân 12 | VDD_IO — I/O supply / decoupling |
| Chân 13 | TEST — Test / bypass mode |
| Chân 14 | MODSEL — Modulation mode select |
| Chân 15 | NC — Not connected (per datasheet) |
| Chân 16 | NC — Not connected (per datasheet) |
Ứng dụng tiêu biểu
MC44BS373CAD phù hợp cho 6 Áp dụngs: VCR RF Output Stage, Satellite / Terrestrial Set-Top Box Modulator, DVD Player Composite-to-RF Conversion, Game Console RF Output, CCTV / Security Observation System Modulator, Cable-TV Headend Test Modulator.
VCR RF Output Stage
The MC44BS373CAD's 82 dBuV typical TV output level and PLL-programmed carrier make it ideal for the RF modulator block of a VCR, where composite video from the playback head stack and audio from the hi-fi or linear track must be upconverted to a standard analog-TV channel. The 16-pin SOIC footprint fits easily into the crowded VCR main board alongside the deck mechanics, and the I2C bus lets the VCR microcontroller re-tune the output channel during install menus.
Được đề xuất
Satellite / Terrestrial Set-Top Box Modulator
Set-top boxes typically need an analog-TV fallback output to feed legacy televisions, and the MC44BS373CAD's multi-standard support (PAL B/G, D/K, M/N, L and NTSC M) lets one BOM serve every regional market. The integrated PLL removes the manual channel-adjustment trimmers that earlier discrete modulators required, simplifying factory alignment. Programmed via I2C, the carrier frequency can be moved at install time to match the TV's expected input channel.
Được đề xuất
DVD Player Composite-to-RF Conversion
DVD players that lack an HDMI input on the target TV need a baseband-to-RF modulator, and the MC44BS373CAD combines the audio subcarrier generator, video modulator, and PLL synthesizer into a single IC. The 82 dBuV output drives the antenna input of any analog TV without an external RF amplifier. The 3.3 V / 5 V compatible I2C bus interfaces directly to the DVD player's main microcontroller without level shifters.
Được đề xuất
Game Console RF Output
Legacy game consoles that need to drive analog televisions benefit from the MC44BS373CAD's stable PLL that holds channel lock across temperature and supply variations. The wide multi-standard coverage means a single game console SKU can be sold in PAL and NTSC regions by simply re-programming the I2C registers. Compared with a discrete modulator, the integrated IC saves roughly 25 to 30 components on the BOM.
Được đề xuất
CCTV / Security Observation System Modulator
CCTV head-ends that need to back-feed an analog TV monitor from a digital video recorder benefit from the MC44BS373CAD's standard TV output level of 82 dBuV, which is the precise level expected at the antenna input of an analog receiver. The PLL programming permits remote channel change from the DVR's microcontroller when surveillance operators switch views. The 0 to +85 C operating range covers most indoor security installations.
Được đề xuất
Cable-TV Headend Test Modulator
Bench and field technicians use the MC44BS373CAD as a known-good reference modulator for testing analog-TV receivers and headend gear. The I2C programmability lets the test set sweep channels quickly to characterize TV tuner sensitivity across the band. The PLL's low phase noise contributes to a clean test signal that does not mask receiver-side impairments.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho MC44BS373CAD — 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 | MC44CC373 | MC44CC374 | MC44BS374CAEF | MC44BS373CAFC | MC44BS373CAEF |
|---|---|---|---|---|---|---|
| Package | 16-SOIC (SO16NB) | 16-SOIC (SO16NB) - same | 16-SOIC (SO16NB) - same | 16-SOIC (SO16NB) - same | 16-SOIC (SO16NB) - same | 16-SOIC (SO16NB) - same |
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Function | NTSC/PAL UHF/VHF Modulator | NTSC/PAL UHF/VHF Modulator (newer) | NTSC/PAL UHF/VHF Modulator (newer) | NTSC/PAL UHF/VHF Modulator (legacy) | NTSC/PAL UHF/VHF Modulator (legacy) | NTSC/PAL UHF/VHF Modulator (legacy) |
| TV Output Level | 82 dBuV typical | 82 dBuV typical | 82 dBuV typical | 82 dBuV typical | 82 dBuV typical | 82 dBuV typical |
| Control Interface | I2C, 5 V and 3.3 V compatible | I2C, 5 V and 3.3 V compatible | I2C, 5 V and 3.3 V compatible | I2C, 5 V and 3.3 V compatible | I2C, 5 V and 3.3 V compatible | I2C, 5 V and 3.3 V compatible |
| Lead-Free | Yes (CAD suffix) | Yes | Yes | Yes | No (non-lead-free) | Yes |
| Generation | Legacy (BS373 family) | Current (CC373 family) | Current (CC374 family) | Legacy (BS374 family) | Legacy (BS373 family) | Legacy (BS373 family) |
| Lifecycle Status | Last-time-buy | Active | Active | Last-time-buy | Last-time-buy | Last-time-buy |
Bảo phân biệt quan trọng
- Current-generation successor with lower power (vsMC44CC373)
- Pin-compatible legacy family sibling (vsMC44BS374CAEF)
- Original non-lead-free variant available (vsMC44BS373CAFC)
Ghi chú thiết kế
The RF output pin (pin 10) must drive a 75 ohm network that is laid out as a controlled-impedance trace to the antenna connector. Place the 75 ohm termination resistors and DC-blocking capacitor as close to the IC pin as possible, and keep the RF trace short and straight. The pin-1 dot marker on the SO16NB identifies the location of pin 1 - verify orientation before soldering, because reversing the IC will short VDD to ground on first power-up.
Decouple VDD (pin 11) and VDD_IO (pin 12) with 100 nF ceramic capacitors placed within 2 mm of the pins. The MC44BS373CAD's PLL is sensitive to supply ripple that appears as FM noise on the RF output. Add a 10 uF bulk capacitor near the IC for low-frequency decoupling. A ferrite bead in series with the VDD trace can further attenuate switching-supply noise from upstream regulators.
The CVBS input (pin 1) requires a 75 ohm terminated video source. A series 75 ohm resistor and AC-coupling capacitor at the IC pin set the proper source impedance and DC bias. Audio input (pin 2) similarly needs proper source impedance and DC blocking. The external reference resonator on pins 7 and 8 determines the carrier frequency step - any drift in this resonator directly translates into channel offset on the TV, so use a high-stability part.
Do not program the I2C address to a value that conflicts with other devices on the same bus - the ADDR pin (pin 5) selects between the two supported slave addresses, and a conflict will lock up both devices. The TEST pin (pin 13) must be left in its default state for normal operation; pulling it high enables factory test mode. Verify the MODSEL pin (pin 14) configuration matches the desired audio subcarrier mode for your target standard.
Thông tin tuân thủ
RoHS compliance confirmed via the CAD suffix (lead-free shipping form). REACH, halogen-free, and conflict-minerals status were not present in the verified distributor data and should be requested from NXP's full material declaration.
