My Inquiry
My Account
STMicroelectronics M74HCT573B1R
- Part No.:
- M74HCT573B1R
- Manufacturer:
- STMicroelectronics
- Category:
- Latches
- Package:
- 20-DIP (0.300", 7.62mm)
- Datasheet:
-
M74HCT573B1R.pdf
- Description:
- IC LATCH OCTAL D-TYPE 20-DIP
- Quantity:
- Payment:
- Shipping:
Inventory:2,565
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
M74HCT573B1R from STMicroelectronics is a high-speed CMOS octal D-type latch with 3-state non-inverting outputs, designed for bus-oriented data latching in TTL- and NMOS-compatible systems. It features 21 ns typical propagation delay (LE→Q), 6 mA minimum output drive, 4 µA max quiescent current at 25°C, and operates across 4.5–5.5 V supply. Used in microcontroller address/data bus isolation and memory interface control.
For engineers reviewing the M74HCT573B1R datasheet, M74HCT573B1R pinout, M74HCT573B1R application, or M74HCT573B1R equivalent, key selection criteria include 3-state output timing (tPZL/tPHZ ≤ 38 ns), latch enable setup/hold times (ts = 4 ns, th = 5 ns), and guaranteed VIH/VIL thresholds (2.0 V / 0.8 V) for robust TTL interfacing.
Technical Context
The M74HCT573B1R implements an edge-triggered latch function controlled by asynchronous LE (latch enable) and OE (output enable) inputs. Its dual-control architecture allows transparent data flow when LE is high, precise level-capture on LE falling edge, and independent 3-state output control via active-low OE.
Designed using silicon gate C2MOS technology, it delivers balanced tPLH ≈ tPHL propagation delays and symmetrical |IOH| = IOL ≥ 6 mA output impedance-enabling bidirectional bus loading predictability and minimizing signal distortion in shared-data-path applications.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Propagation Delay (LE→Q) | 21 ns typ. at VCC = 4.5 V, CL = 50 pF - enables ≤47.6 MHz latch control in synchronous bus systems |
| Output Drive Strength | ≥6 mA IOH/IOL - supports direct driving of 10 LS-TTL loads or 20 CMOS loads without buffering | Input Voltage Thresholds | VIH ≥ 2.0 V, VIL ≤ 0.8 V - ensures reliable logic-level recognition from standard TTL outputs |
| Quiescent Supply Current | 4 µA max at TA = 25°C - minimizes standby power in battery-backed or low-power hold modes |
| Operating Temperature Range | −55°C to +125°C - qualified for industrial and extended-temperature embedded control environments |
| 3-State Leakage Current | ±10 µA max at −55°C to +125°C - prevents unintended bus contention during high-impedance state |
Pinout & Package
Package: Plastic DIP-20 (0.300" width), JEDEC MS-001, body dimensions 25.4 × 8.5 mm.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (OE) | Active-low 3-state output enable | Drives all Q0–Q7 into high-impedance when high; enables normal logic output when low |
| 2–9 (D0–D7) | Data inputs | Asynchronous inputs latched on LE falling edge; TTL-compatible voltage thresholds |
| 11 (LE) | Latch enable | High = transparent mode (Q follows D); low = latch mode (Q holds last D value) |
| 12–19 (Q0–Q7) | 3-state non-inverting outputs | Drive bus lines directly; high-Z state eliminates contention during multi-driver arbitration |
| 10 (GND) | Ground reference | 0 V return path for all internal logic and I/O; must be low-inductance connection |
| 20 (VCC) | Positive supply | 4.5–5.5 V operation; decoupling capacitor required within 1 cm of pin for noise immunity |
Key Features
| Feature | Design Value |
|---|---|
| Pin- and function-compatible with 74LS573 | Direct drop-in replacement for legacy TTL latch designs without PCB redesign |
| Balanced tPLH/tPHL propagation | Minimizes skew between rising/falling output transitions for clean bus timing margins |
| Symmetrical output impedance | Ensures matched rise/fall times and consistent signal integrity across all 8 outputs |
| ESD protection on all inputs | Withstands ±2 kV HBM per IEC 61000-4-2 - reduces need for external transient suppression |
Applications
| Microcontroller Address Latching | Memory Data Bus Isolation |
|---|---|
Use Scenario: Holding multiplexed AD0–AD7 address/data lines during 8051 or Z80 CPU read/write cycles. IC Role / Device Role / Timing Role: Acts as address latch to separate time-multiplexed bus signals into dedicated address and data paths. Use Value: Enables use of 8-bit microcontrollers with external RAM/ROM using single 8-bit bus, reducing pin count and PCB routing complexity. | Use Scenario: Isolating SRAM or EPROM data lines from shared system data bus during inactive memory cycles. IC Role / Device Role / Timing Role: Provides 3-state-controlled data path gating synchronized to memory chip select and read/write strobes. Use Value: Prevents bus contention between multiple memory devices and peripherals sharing same data lines. |
| Peripheral Interface Buffering | Industrial I/O Expansion |
Use Scenario: Interfacing parallel LCD controllers or printer ports to microcontroller GPIO buses. IC Role / Device Role / Timing Role: Buffers and latches parallel control/data signals with precise LE timing aligned to peripheral handshaking. Use Value: Absorbs timing mismatches between fast MCU and slower peripherals while maintaining signal integrity. | Use Scenario: Expanding digital I/O capability in PLC modules or sensor concentrators using parallel I/O expanders. IC Role / Device Role / Timing Role: Serves as input capture latch for 8-bit status registers or output driver for 8-bit control signals. Use Value: Supports deterministic sampling of field inputs and synchronized actuator updates in real-time control loops. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar octal latch with 3-state output applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN74HCT573N | Same logic function, identical AC/DC specs, but TI package marking and thermal resistance differs slightly (DIP-20, θJA = 65°C/W vs ST's 70°C/W) | No functional difference; validated in same bus-hold and memory interface roles | Select when sourcing from TI-authorized channels or requiring TI-specific qualification documentation |
| 74VHC573N | Higher speed (tPD = 10.5 ns typ.), wider VCC range (2–5.5 V), but lower output drive (±8 mA) and no guaranteed VIH/VIL for TTL compatibility | Not suitable for direct TTL interfacing without level-shifting; better for mixed-voltage or ultra-low-power designs | Choose only if operating below 4.5 V or requiring sub-20 ns propagation - not a drop-in TTL replacement |
Compared with SN74HCT573N, M74HCT573B1R offers identical timing and drive but distinct manufacturing traceability; versus 74VHC573N, it trades raw speed for guaranteed TTL interoperability and higher noise margin in legacy 5 V systems.
Availability
M74HCT573B1R is available at Aetrix Electronics and suitable for microcontroller bus interfacing, memory subsystem isolation, and industrial I/O expansion requiring stable component supply and long-term industrial temperature support.
Supply support for M74HCT573B1R 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
STMicroelectronics is a global semiconductor leader headquartered in Geneva, specializing in automotive, industrial, and power management ICs with broad analog, digital, and mixed-signal portfolios.
The M74HCT573 belongs to ST's high-speed CMOS logic family, engineered specifically for seamless interoperability between modern CMOS systems and legacy TTL/NMOS logic in industrial control and embedded computing.
FAQ
What is the maximum clock frequency supported by M74HCT573B1R?
The M74HCT573B1R is not a clocked register but an edge-triggered latch with no internal clock. Its usable data rate depends on LE pulse width and propagation delay: minimum LE pulse width is 7 ns (typ.) at 4.5 V, supporting effective latch rates up to ~140 MHz in ideal conditions. System-level timing must account for setup/hold (ts = 4 ns, th = 5 ns) and bus settling.
Can M74HCT573B1R operate at 3.3 V?
No. The M74HCT573B1R is specified only for 4.5–5.5 V operation per its Recommended Operating Conditions. At 3.3 V, VIH/VIL thresholds become undefined, output drive collapses below specification, and DC parameters (e.g., VOH) fall outside guaranteed limits - risking logic misreads and bus contention.
Is there a surface-mount version of this part?
Yes. STMicroelectronics offers SOP-20 (M74HCT573M1R) and TSSOP-20 (M74HCT573TTR) variants with identical logic functionality and AC/DC specifications. Pinout and timing are fully compatible; only package dimensions and thermal characteristics differ.
Does M74HCT573B1R require external pull-up resistors on outputs?
No. The 3-state outputs are actively driven high or low when enabled (OE low); pull-ups are unnecessary and may cause excessive current draw during high-impedance state. External termination is only needed for impedance matching on long transmission lines - not for basic logic-level translation or bus driving.
M74HCT573B1R Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- 74HCT
- Package/Case:
- 20-DIP (0.300", 7.62mm)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Logic Type:
- D-Type Transparent Latch
- Circuit:
- 1:8
- Output Type:
- Tri-State
- Voltage - Supply:
- 4.5V ~ 5.5V
- Independent Circuits:
- 1
- Delay Time - Propagation:
- 19ns
- Current - Output High, Low:
- 6mA, 6mA
- Operating Temperature:
- -55°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- 20-DIP
M74HCT573B1R FAQ
1.How can I place an order for M74HCT573B1R through Aetrix?
Please submit a Request for Quotation (RFQ) for M74HCT573B1R 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 M74HCT573B1R reliable?
The price and inventory of M74HCT573B1R are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for M74HCT573B1R is usually 5 days.
3.What payment methods are accepted for M74HCT573B1R?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for M74HCT573B1R transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for M74HCT573B1R?
M74HCT573B1R orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your M74HCT573B1R 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 M74HCT573B1R?
For technical support, including M74HCT573B1R datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your M74HCT573B1R requirements.
6.How does Aetrix verify that M74HCT573B1R is sourced from the original manufacturer or authorized distributors?
All M74HCT573B1R 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 M74HCT573B1R meets industry standards.
7.What is the process for return or replacement of M74HCT573B1R?
All M74HCT573B1R units undergo pre-shipment inspection (PSI). If there is an issue with M74HCT573B1R, 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 M74HCT573B1R part is unused and in its original packaging.
Return procedure for M74HCT573B1R:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
M74HCT573B1R Tags
-
SN74HC573APWR
Texas Instruments
-
SN74HC573ADWR
Texas Instruments
-
SN74AHC573PWR
Texas Instruments
-
SN74HCT573DWR
Texas Instruments
-
SN74HC373N
Texas Instruments
-
SN74HC573AN
Texas Instruments
-
74VHC573MTCX
onsemi
-
MC74LCX573DTR2G
onsemi
-
74AUP1G373GW,125
Nexperia USA Inc.
-
SN74LVC1G373DCKR
Texas Instruments
-
SN74LVC1G373DBVR
Texas Instruments
-
NC7SZ373P6X
onsemi
Tech Hub
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…
LDO regulator guide covering low dropout voltage, power dissipation, thermal design, PSRR, output noise, capacitor stability, adjustable LDO circuits, LDO vs buck converter and datasheet selection chec…
Conditional Access Module guide covering CAM meaning, CI/CI+ interface, smart card authorization, DVB security workflow, TV and set-top box compatibility, internal electronics, ESD protection, connecto…
Guide to electronic component obsolescence covering EOL risk, PCN/PDN notices, last-time buy planning, replacement options, form-fit-function validation, counterfeit risk and BOM lifecycle management.
18650 battery guide covering lithium-ion cell basics, 3.6V/3.7V voltage, 4.2V charging, mAh and Wh capacity, protected cells, chargers, BMS, series-parallel packs, holders, welding and sourcing checks.…
Hall effect sensor guide covering working principle, linear and digital sensors, Arduino circuits, current sensing, speed detection, automotive applications, A3144 examples, signal filtering and datash…
Product Change Notification guide for electronic components, covering PCN meaning, PCN vs PDN/EOL, common change types, risk levels, form-fit-function review, engineering validation, BOM control, LTB/L…
A practical guide to blend door actuators, covering HVAC function, symptoms, location, AC and heater issues, reset and calibration, replacement cost, electrical diagnosis, compatibility checks, and rep…
Engineering guide to Raspberry Pi alternatives, covering chip-level differences, Orange Pi, ROCK, Jetson, Banana Pi, NanoPi, Compute Module, Pico, GPIO, camera, HAT compatibility, and replacement risks…
