SN74LV4052APWR — Dual 4-Channel Analog Multiplexer/Demultiplexer from Texas Instruments

What Is SN74LV4052APWR and How Does It Work?

The SN74LV4052APWR contains two independent 4:1 analog multiplexers in a single package. Each mux has four signal pins (Y0–Y3), one common pin (COM), and two select lines (A and B) shared between both muxes. The INH (inhibit) pin, when driven high, disconnects all channels.

How it's different from a digital bus transceiver: the LV4052 is a passive FET switch. When a channel is enabled, the signal path is just a low-resistance (~75Ω) connection between the Y pin and the COM pin. There's no buffering, no direction control, no clock. The signal passes through as-is — analog voltage, digital bit, doesn't matter. This is fundamentally different from the LVC245, which actively drives its outputs high or low.

Because it's bidirectional, "mux" and "demux" are just labels for how you wire it. In mux mode, four inputs (Y0–Y3) connect to one output (COM). In demux mode, one input (COM) connects to four outputs (Y0–Y3). The silicon doesn't know the difference.

Per the TI datasheet (Rev H, SCDS041H), the device also includes break-before-make switching — when you change channels, the currently selected channel opens before the new one closes. This prevents momentary shorting between two signal sources during switching.

What Are the Specifications of SN74LV4052APWR?

Key Numbers That Matter

• Ron = 75Ω typical (180Ω max at 3V): This is the number that determines whether the LV4052 works in your design. 75Ω is low enough for most ADC inputs (which are typically high-impedance, >10kΩ) and digital signals, but it matters for two scenarios: (1) driving low-impedance loads — if your downstream load is 1kΩ, you lose 7% of your signal across the switch; (2) cascading multiple muxes — each stage adds 75Ω. For audio signals into a high-Z amplifier input, 75Ω is invisible. For a 50Ω RF path, it's a dealbreaker.
• Bandwidth = 50 MHz: Don't confuse this with digital data rate. At 50 MHz -3dB, the switch can pass a 10 MHz square wave with decent fidelity (you need roughly 5× the fundamental frequency for the 5th harmonic). For I2C at 400 kHz, UART at 115.2 kbps, or SPI at a few MHz, the bandwidth is more than enough. For 100 Mbps Ethernet — no.
• Break-before-make = 4 ns: Per the TI datasheet (Rev H), when you switch channels, the old channel opens ~4 ns before the new one closes. This 4 ns gap prevents the two signal sources from being momentarily shorted together. Without this feature, switching from Y0 to Y1 would briefly connect both to COM — potentially damaging your signal sources if one is driving high and the other low.

When Should You Use (and NOT Use) SN74LV4052APWR?

✔ Use SN74LV4052APWR when:

• You need to share one ADC across multiple analog sensors. This is the classic 4052 use case. Two 4:1 muxes → up to 8 single-ended inputs into just 2 ADC channels, selected by 2 GPIO pins. No firmware overhead beyond toggling A/B and waiting 14 ns for the switch to settle.
• You're switching UART, I2C, or SPI lines between peripherals. The switch is bidirectional and transparent — it doesn't care about protocol. Just keep your signal voltages within the supply rails and account for the 75Ω series resistance.
• You need analog signal routing (audio, sensor, low-speed video). The 50 MHz bandwidth handles audio (20 Hz–20 kHz) with headroom to spare. For composite video (~6 MHz), you're within the flat part of the frequency response.
• You're doing automated test or calibration where signal paths need to be reconfigured. The INH pin gives you a single-wire "disconnect all" — pull it high and all channels go open. Useful for self-test routines.

✘ Don't use SN74LV4052APWR when:

• You're routing high-frequency signals (>10 MHz). At 50 MHz -3dB, your 20 MHz clock is already down 1 dB and the harmonics that give it a square edge are severely attenuated. For RF or fast digital, use a dedicated RF switch or a newer mux like the TMUX1309 (500 MHz BW).
• Your load impedance is under 1kΩ. With 75Ω Ron in series, you create a voltage divider. Into a 600Ω load (common in pro audio), you lose 11% of your signal. For low-impedance loads, look at the TMUX series (sub-10Ω Ron) or use a buffer amplifier after the mux.
• You need I2C-controlled channel selection. The LV4052 uses GPIO pins (A, B, INH) for control. If you're out of GPIOs or want to control the mux over I2C, TI's TCA9546A (4-channel I2C mux) or TCA9548A (8-channel) is the better choice — they're controlled entirely over the I2C bus.
• Your signal voltage exceeds VCC. The signal on any Y or COM pin must stay between GND and VCC. Apply 5V to a Y pin when VCC is 3.3V and you'll forward-bias the internal ESD protection diodes — the device may survive for a while but it's operating outside the absolute maximum ratings.

What Are the Alternatives to SN74LV4052APWR?

Pick TMUX1309PWR when: You're starting a new design and want the better part. Lower Ron (59Ω), vastly higher bandwidth (500 MHz), 1.8V-compatible logic inputs, injection-current control, and a wider temperature range — all for roughly the same price as the LV4052. The TMUX1309 is essentially TI's modern replacement for the LV4052 in new designs.

Pick CD74HC4052PWR when: You need a higher supply voltage (up to 6V) or wider temperature range (-55°C to +125°C). The HC4052 is the legacy high-voltage version — slower (60 ns switching), higher Ron (160Ω), but proven in industrial and automotive systems for decades. From our distribution data (2025–2026), the HC4052 still moves in volume for 5V-centric designs.

Pick 74LV4052PW (Nexperia) when: You're second-sourcing. Nexperia's LV4052 variant is functionally identical — same pinout, same TSSOP-16 package, comparable Ron and switching speed. The 200 MHz bandwidth is a notable improvement over TI's 50 MHz. Availability from Nexperia has been solid in the Shenzhen market.

Pricing & Availability

Contact ICMASS for current pricing. This is a commodity analog switch IC — pricing is competitive at volume. We stock the TSSOP-16 package with full traceability. Pin-compatible alternatives (TMUX1309PWR, 74LV4052PW from Nexperia) also available for multi-sourcing.

What Are the Typical Applications of SN74LV4052APWR?

ADC Input Expansion

A microcontroller with 2 ADC channels can read 8 analog sensors through one LV4052 — four sensors per mux channel, selected by 2 GPIOs. The 75Ω Ron adds negligible error when the ADC input impedance is >10kΩ (which it usually is). Per the TI datasheet (Rev H), the 14 ns switching time means you can scan all 8 channels in under 200 ns — plenty fast for temperature, pressure, or light sensors that update on millisecond timescales.

I2C Bus Multiplexing

A single I2C master can talk to four sets of I2C slaves through one mux channel (SDA + SCL through two of the four Y paths). But here's the catch: place pull-up resistors on both sides of the switch. Without pull-ups on the slave side, the bus floats during the break-before-make transition and can glitch. Without pull-ups on the master side, the bus floats when INH is asserted. This is the number one support question on TI E2E for this part.

UART Peripheral Switching

A microcontroller with one UART can communicate with four peripherals (GPS, Bluetooth, RS-485, debug console) through one LV4052 channel. TX from MCU → COM, Y0–Y3 → each peripheral's RX. RX from each peripheral → second mux channel's Y0–Y3, COM → MCU RX. Two GPIOs select the active peripheral. At 115.2 kbps, the 50 MHz bandwidth is overkill in the best way.

Audio Source Selection

Route one of four audio inputs to an amplifier through a single mux channel. The 75Ω Ron into a typical 10k–47kΩ amplifier input introduces <1% signal loss. Crosstalk between channels is -45 dB at 1 MHz, which means at audio frequencies (1 kHz) it's well below -60 dB — effectively silent.

Automated Test Equipment

In production test fixtures, the LV4052 routes calibration signals, stimulus waveforms, and measurement buses to different points on a DUT. The INH pin is particularly useful here — assert it during power-up to ensure nothing is connected until the test sequence explicitly enables a path.

Frequently Asked Questions About SN74LV4052APWR

Q1: Is SN74LV4052APWR bidirectional?

A: Yes. Each channel is a passive FET switch — it conducts equally well in both directions. Connect four signals to Y0–Y3 and route to COM (mux mode), or connect one signal to COM and route to Y0–Y3 (demux mode). The device doesn't care which direction current flows, as long as voltages stay within the supply rails. This is confirmed on TI E2E forum in multiple threads about I2S and UART applications.

Q2: Can I use SN74LV4052APWR to mux I2C signals?

A: Yes, but you must place pull-up resistors on both sides of the switch — the master side and each slave bus segment. Without slave-side pull-ups, the I2C lines float during the break-before-make transition between channels, causing glitches that can be interpreted as START/STOP conditions. This is the single most frequently discussed topic on TI E2E for this part. If you're designing a new I2C mux from scratch and have I2C bus available for control, TI recommends the TCA9546A instead — it's purpose-built for I2C with built-in level translation.

Q3: What's the difference between mux and demux mode?

A: There is no electrical difference. The LV4052 is a bidirectional switch. "Mux" means N inputs → 1 output (you connect multiple signal sources to Y pins and select which one reaches COM). "Demux" means 1 input → N outputs (you connect one signal source to COM and select which Y pin it routes to). Same hardware, different wiring. Per the TI datasheet (Rev H, SCDS041H), both configurations are equally valid.

Q4: Why does the output glitch when I switch channels?

A: This is inherent to the break-before-make switching mechanism. When you change A/B select lines, the currently active channel opens (~4 ns before the new channel closes), creating a brief moment where COM is connected to nothing. If COM has parasitic capacitance, the voltage drifts during this gap. The glitch duration is typically under 10 ns. Mitigation: place a small holding capacitor (10–100 pF) on COM to reduce drift, or add a downstream sample-and-hold that ignores the switching transient period. This behavior is documented on TI E2E and is common to all break-before-make analog switches.

Q5: Can I apply 5V signals when VCC is 3.3V?

A: No — this is a hard limit. Signal voltages on any Y or COM pin must not exceed VCC. Applying 5V to a signal pin when VCC is 3.3V forward-biases the internal ESD protection diodes and forces current into the VCC rail. This can cause latch-up, damage the device, or at minimum cause erratic behavior. If you need 5V signal handling at 3.3V VCC, use a switch rated for signals above the supply (like the TMUX1309 with injection-current control) or add external clamping diodes.

Q6: How much signal do I lose across the switch?

A: It depends on your load impedance. The switch behaves like a 75Ω resistor in series with your signal. If your downstream load is 10kΩ, the voltage divider is 75 / (75 + 10000) = 0.74% loss — negligible. If your load is 600Ω, the divider is 75 / (75 + 600) = 11% loss — you'll notice that. For low-impedance loads (<1kΩ), buffer the output with an op-amp voltage follower to present a high-impedance load to the switch.

Q7: What is the INH pin for?

A: INH (inhibit) is a global disable. When driven high, all channels are disconnected regardless of the A/B select lines. When driven low, the channel selected by A/B is active. Use INH for: (1) power-up sequencing — assert INH high during power-up so no unintended paths are active; (2) ganging multiple LV4052s — tie all INH pins together for a single "all off" control; (3) self-test — disconnect all external signals and inject a known test voltage. Per the TI datasheet (Rev H), INH overrides A and B — when INH = high, the state of A/B doesn't matter.

Q8: Can I use both mux channels independently?

A: Yes — the two SP4T switches are completely independent except that they share the A, B, and INH control pins. Both channels always select the same Y-number (Y0, Y1, Y2, or Y3). You cannot have channel 1 on Y0 while channel 2 is on Y2 — the shared A/B lines prevent independent channel selection. If you need fully independent control, use two separate LV4052s with separate A/B lines, or use a device with independent select pins.

Q9: What happens if INH and all channels are off — is there leakage between Y pins?

A: Per the TI datasheet (Rev H), off-state leakage current (IS off) is 100 nA max at 25°C. In practice, the off-isolation is excellent — adjacent channels at different voltages will not interfere with each other under normal conditions. At elevated temperatures (>85°C), leakage increases (check the datasheet curves), but for room-temperature operation, crosstalk between deselected channels is dominated by PCB layout, not the IC.

Q10: Is SN74LV4052APWR a drop-in replacement for CD4052?

A: Pinout — yes. Both use the industry-standard 16-pin 4052 pinout (A at pin 10, B at pin 9, INH at pin 6, etc.). Electrical specs — very different. The CD4052 runs at 3–20V with Ron of 240Ω (at 5V). The LV4052 runs at 2–5.5V with Ron of 75Ω. If your design runs at 5V, you can swap them, but the lower Ron and faster switching of the LV4052 may change circuit behavior — particularly in RC timing circuits or places where the switch resistance was part of the original design calculation.