My Inquiry
My Account
Texas Instruments CD74HC423MT
- Part No.:
- CD74HC423MT
- Manufacturer:
- Texas Instruments
- Category:
- Multivibrators
- Package:
- 16-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
CD74HC423MT.pdf
- Description:
- IC MULTIVIBRATOR 25NS 16SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:886
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
CD74HC423MT from Texas Instruments is a dual retriggerable monostable multivibrator with independent resets, designed for precise pulse generation and timing control in digital systems. It features Schmitt-trigger inputs on both A and B trigger pins, buffered Q and Q̅ outputs, and external RC timing (RX/CX) enabling adjustable pulse widths from microseconds to seconds. It operates across -55°C to +125°C and supports 2V–6V supply, making it suitable for industrial control logic, debounce circuits, and programmable delay generators.
For engineers reviewing the CD74HC423MT datasheet, CD74HC423MT pinout, CD74HC423MT application, or CD74HC423MT equivalent, this page delivers verified electrical specs, SOIC-16 package details, timing behavior under retriggering and reset conditions, and validated alternative options for design-in flexibility and long-term supply continuity.
Technical Context
The CD74HC423MT implements two independent monostable multivibrators, each with separate A (trailing-edge), B (leading-edge), and R (active-low reset) inputs. Unlike the '123 family, the '423 variant does not support negative-to-positive reset edge triggering - only active-low level reset termination of the output pulse.
Timing is externally set via RX and CX; pulse width follows tW = 0.45·RXCX at VCC = 5V. Propagation delays (e.g., 64 ns max A→Q at 4.5V, 25°C) and retrigger time (76 ns max with RX=10kΩ, CX=0) are specified over full temperature range, ensuring predictable behavior in harsh environments.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Function | Dual retriggerable monostable multivibrator with independent resets |
| Supply Voltage Range | 2V–6V - enables direct interface with mixed-voltage logic systems without level shifters |
| Operating Temperature | -55°C to +125°C - qualified for aerospace, military, and under-hood automotive applications |
| Output Pulse Width | Adjustable via external RX/CX; tW = 0.45·RXCX (e.g., 45 µs with 10 kΩ/10 nF at 5V) |
| Input Compatibility | Schmitt-trigger A/B inputs - reject noise and ensure clean edge detection regardless of input rise/fall time |
| Reset Behavior | Active-low level reset (R) terminates output pulse immediately - no edge sensitivity, unlike '123 types |
| Propagation Delay | 64 ns max (A/B/R → Q, VCC=4.5V, TA=25°C) - supports high-speed timing coordination |
Pinout & Package
CD74HC423MT is housed in a 16-pin SOIC (Small Outline Integrated Circuit) package, 7.5 mm wide, with 1.27 mm pitch and gull-wing leads. Thermal resistance θJA = 73°C/W enables reliable operation up to 125°C ambient with minimal heatsinking.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1A, 2A | Trailing-edge trigger input | Activates monostable on falling edge; Schmitt-triggered for noise immunity |
| 1B, 2B | Leading-edge trigger input | Activates monostable on rising edge; Schmitt-triggered for noise immunity |
| 1R, 2R | Active-low reset input | Forces Q low and Q̅ high immediately when pulled low - level-sensitive, not edge-triggered |
| 1Q, 2Q | Inverted output | Complementary to Q; buffered for fanout of 10 LSTTL loads |
| 1Q̅, 2Q̅ | Non-inverted output | Primary timing output; buffered for fanout of 10 LSTTL loads |
| 1CX, 2CX | External timing capacitor connection | Connects to external CX; sets pulse width with RX per channel |
| 1RXCX, 2RXCX | External timing resistor connection | Connects to external RX; forms RC network with CX to define tW |
| VCC | Positive supply | 2V–6V operation; decoupling required near pin for stable timing |
| GND | Ground reference | Common return for all signals and power; must be low-impedance |
Key Features
| Feature | Design Value |
|---|---|
| Retriggerable operation | Each monostable extends its output pulse upon new A/B trigger while Q is high - enables variable-duration gating |
| Independent dual channels | Two fully isolated monostables share only VCC and GND - eliminates crosstalk in multi-signal timing |
| Overriding reset | Active-low R input forces immediate Q low regardless of current state - critical for fail-safe system control |
| Wide pulse width range | RC-tunable from sub-microsecond to seconds - supports both precision clock stretching and long-delay functions |
| High noise immunity | NIL/NIH = 30% of VCC at 5V - ensures robust operation in electrically noisy industrial environments |
Applications
| Industrial Motor Control | Automotive Sensor Debounce |
|---|---|
|
Use Scenario: Generating fixed-duration enable pulses for stepper motor drivers during direction change sequences. IC Role / Device Role / Timing Role: Dual monostable provides synchronized gate-enable and direction-set timing windows, preventing shoot-through during commutation. Use Value: Precise, temperature-stable pulse width (±2% match between channels) ensures consistent motor torque and reduces EMI from switching transients. |
Use Scenario: Eliminating mechanical contact bounce in vehicle door latch or seat position sensors. IC Role / Device Role / Timing Role: Each monostable filters one sensor signal using leading-edge (B) trigger and RC-determined hold-off time (>10 ms). Use Value: Schmitt-trigger inputs reject ESD-induced glitches; -55°C to +125°C rating guarantees reliability across cabin and under-hood environments. |
| Test Equipment Pulse Generation | Programmable Logic Timing Extension |
|
Use Scenario: Creating calibrated delay intervals in automated test fixtures for validating microcontroller interrupt response. IC Role / Device Role / Timing Role: One-shot configured with 100 kΩ/100 pF yields ~4.5 µs pulse; second channel used for gated measurement window. Use Value: Matched propagation delays (<±2% between channels) enable sub-10 ns timing correlation accuracy across dual signal paths. |
Use Scenario: Extending finite-state machine dwell times in legacy FPGA-based controllers where internal timers lack resolution. IC Role / Device Role / Timing Role: External RC network (1 MΩ/100 nF) sets 45 ms pulse width to replace software delays, freeing CPU cycles. Use Value: Retrigger capability allows dynamic pulse extension based on real-time events - impossible with non-retriggerable timers. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual monostable multivibrator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| CD74HC123MT | Supports both trailing- and leading-edge reset triggering (R input responds to negative-going edge); otherwise identical pinout and timing | Required where reset must be edge-triggered (e.g., synchronous digital systems with clock-aligned reset assertion) | Select CD74HC123MT if edge-sensitive reset is needed; CD74HC423MT is preferred for simpler level-reset control |
| SN74LV221AD | Lower voltage range (2V–5.5V), higher speed (22 ns max tPLH), but no Schmitt-trigger inputs and narrower temp range (-40°C to +125°C) | Better suited for battery-powered portable devices needing fast, low-voltage timing - not for high-noise or extended-temp use | Choose SN74LV221AD only for cost-optimized consumer designs with benign EMI and moderate temperature requirements |
Compared with CD74HC123MT and SN74LV221AD, the CD74HC423MT offers superior noise immunity via Schmitt-trigger inputs and extended temperature support, making it the optimal choice for industrial and automotive timing where deterministic reset behavior and environmental ruggedness are mandatory.
Availability
CD74HC423MT is available at Aetrix Electronics and suitable for industrial motor control, automotive sensor conditioning, and test equipment requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for CD74HC423MT includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and logic solutions, with decades of heritage in high-reliability logic families.
The CD74HC423MT belongs to TI's 74HC high-speed CMOS logic series, engineered for low-power, noise-immune timing functions in mission-critical industrial and defense systems.
FAQ
What is the key functional difference between CD74HC423MT and CD74HC123MT?
The CD74HC423MT uses level-sensitive active-low reset (R), terminating the output pulse immediately when R is pulled low. In contrast, CD74HC123MT supports edge-triggered reset - its R input responds to a negative-going transition. Both share identical pinout, timing equations, and SOIC-16 packaging, but CD74HC423MT simplifies reset logic in systems where level control suffices.
Can CD74HC423MT operate at 3.3V supply voltage?
Yes, CD74HC423MT supports 2V–6V operation, including 3.3V. At VCC = 3.3V, VIH(min) = 2.31V and VIL(max) = 0.99V per HC specifications, ensuring compatibility with 3.3V LVTTL and CMOS logic families. Propagation delays increase slightly versus 5V operation but remain within datasheet limits across -55°C to +125°C.
What is the minimum external capacitance (CX) supported by CD74HC423MT?
The datasheet specifies CX ≥ 0 pF for CD74HC423MT - meaning no external capacitor is strictly required. However, practical implementation mandates a small capacitor (≥10 pF) for stability and noise rejection. With CX = 0 pF, timing becomes highly sensitive to stray capacitance and cannot be accurately predicted; TI recommends CX ≥ 10 pF for repeatable pulse width control.
Does CD74HC423MT support retriggering during an active output pulse?
Yes, CD74HC423MT is fully retriggerable: applying a valid trigger (A or B) while Q is high extends the output pulse width by tW from the new trigger edge. This behavior enables dynamic pulse stretching - for example, maintaining a gate signal while successive encoder pulses arrive - and is confirmed in the truth table and timing diagrams of the official datasheet.
Is the SOIC package of CD74HC423MT RoHS-compliant and lead-free?
Yes, CD74HC423MT is RoHS-compliant and features NiPdAu (NIPDAU) lead finish. Per TI's packaging addendum, the SOIC (D) package carries "Yes" for RoHS and "NIPDAU" for lead finish, with MSL Level-1 rating (unlimited floor life at ≤30°C/60% RH). The part marking "HC423M" appears on the device body, confirming full compliance with EU RoHS Directive 2011/65/EU.
CD74HC423MT Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- 74HC
- Package/Case:
- 16-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Logic Type:
- Monostable
- Independent Circuits:
- 2
- Schmitt Trigger Input:
- No
- Propagation Delay:
- 25 ns
- Current - Output High, Low:
- 5.2mA, 5.2mA
- Voltage - Supply:
- 2 V ~ 6 V
- Operating Temperature:
- -55°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-SOIC
CD74HC423MT FAQ
1.How can I place an order for CD74HC423MT through Aetrix?
Please submit a Request for Quotation (RFQ) for CD74HC423MT on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for CD74HC423MT reliable?
The price and inventory of CD74HC423MT are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for CD74HC423MT is usually 5 days.
3.What payment methods are accepted for CD74HC423MT?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for CD74HC423MT transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for CD74HC423MT?
CD74HC423MT orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your CD74HC423MT order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for CD74HC423MT?
For technical support, including CD74HC423MT datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your CD74HC423MT requirements.
6.How does Aetrix verify that CD74HC423MT is sourced from the original manufacturer or authorized distributors?
All CD74HC423MT products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that CD74HC423MT meets industry standards.
7.What is the process for return or replacement of CD74HC423MT?
All CD74HC423MT units undergo pre-shipment inspection (PSI). If there is an issue with CD74HC423MT, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The CD74HC423MT part is unused and in its original packaging.
Return procedure for CD74HC423MT:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
CD74HC423MT Tags
-
SN74LVC1G123DCUR
Texas Instruments
-
CD4047BM96
Texas Instruments
-
SN74LVC1G123DCTR
Texas Instruments
-
CD74HC221M96
Texas Instruments
-
CD14538BE
Texas Instruments
-
SN74LVC1G123YZPR
Texas Instruments
-
SN74LVC1G123DCUT
Texas Instruments
-
MC14538BDR2G
onsemi
-
74VHC123AMX
onsemi
-
LTC6993CS6-2#TRMPBF
Analog Devices Inc.
-
LTC6993CS6-3#TRMPBF
Analog Devices Inc.
-
LTC6993CS6-1#TRMPBF
Analog Devices Inc.
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
