CD4066BM96

The CD4066BM96 from Texas Instruments is a quad bilateral switch intended for the transmission or multiplexing of analog or digital signals. It contains four independent single-pole single-throw (SPST) switches, each controlled by its own control input. The device is pin-compatible with the CD4016B but offers significantly lower on-resistance (125Ω vs. 500Ω at 15V) and flatter on-resistance over the signal input range. The 10pA off-state leakage current at 25°C makes it suitable for precision sample-and-hold and integrator circuits. The 40MHz bandwidth and -50dB crosstalk support video signal switching. The bidirectional signal path allows use as either a switch or a multiplexer. The matched control-input-to-signal-output capacitance reduces output transients during switching. The M96 suffix denotes the SOIC-14 package with tape-and-reel packaging.

Each of the four switches in the CD4066BM96 consists of a parallel n-channel and p-channel MOSFET pair forming a transmission gate. When the control input (nC) is high (near VDD), both the n-channel and p-channel MOSFETs conduct, creating a low-impedance bidirectional path between the switch I/O pins. The parallel n/p structure is critical because the n-channel conducts well for signals near VSS but poorly near VDD, while the p-channel conducts well near VDD but poorly near VSS. Together, they provide a relatively flat on-resistance (125Ω typical at 15V) across the full signal range from VSS to VDD. When the control input is low (near VSS), both MOSFETs are off and the switch presents high impedance. The extremely low 10pA off-state leakage results from the fully complementary CMOS structure where both transistors are completely cutoff. The bidirectional nature comes from the symmetric MOSFET structure: current can flow in either direction through the transmission gate. The -50dB crosstalk specification is achieved because each switch is isolated by the high-impedance off-state of adjacent switches and by layout techniques that minimize parasitic coupling. For sample-and-hold applications, the CD4016B is recommended because its higher but more consistent off-state leakage provides more predictable charge injection characteristics.

CD4066BM96 uses the SOIC-14 surface-mount package: VDD at Pin 14, VSS at Pin 7. Four independent bilateral switches: SW1 (Pin 1 in/out, Pin 2 in/out, Pin 13 control), SW2 (Pin 3 in/out, Pin 4 in/out, Pin 5 control), SW3 (Pin 8 in/out, Pin 9 in/out, Pin 6 control), SW4 (Pin 10 in/out, Pin 11 in/out, Pin 12 control). Each switch conducts bidirectionally when its control pin is HIGH. The bilateral nature means signal can flow in either direction — there is no dedicated input or output. On-resistance is typically 50Ω at 15V supply and 270Ω at 5V. For lower on-resistance, 74HC4066 provides 35Ω at 5V. The BM96 suffix denotes SOIC-16 tape-and-reel from TI.

• Audio Routing: <0.5% THD and 40MHz bandwidth pass audio signals without audible distortion; 4 switches handle L/R routing
• Video Switching: 40MHz bandwidth and -50dB crosstalk handle composite video; low Ron preserves signal amplitude
• Programmable Filters: Switch different R/C networks in and out of active filter circuits under MCU control
• Chopper Applications: 10pA off-leakage minimizes charge injection errors in chopper-stabilized amplifiers
• Mux Networks: 4 independent switches with individual control build custom multiplexer configurations beyond fixed 8:1 or 4:1 muxes

CD4066 is the CMOS 4000-series quad bilateral switch operating over the wide 3-18V supply range. The HEF4066 (NXP) and MC144066 (onsemi) are direct pin-compatible equivalents. For higher speed at the cost of narrower voltage range, the 74HC4066 HC/HCT families offer significantly faster propagation delay and lower power consumption at 2-6V. Surface-mount versions use the BM/M suffix (SOIC); through-hole versions use the BE suffix (DIP).