My Inquiry
My Account
Texas Instruments SN75477DE4G4
- Part No.:
- SN75477DE4G4
- Manufacturer:
- Texas Instruments
- Package:
- -
- Datasheet:
-
SN75477DE4G4.pdf
- Description:
- NAND GATE BASED PERIPHERAL DRIVE
- Quantity:
- Payment:
- Shipping:
Inventory:2,400
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SN75477DE4G4 from Texas Instruments is a dual NAND peripheral driver IC designed for high-voltage, high-current switching in electromechanical interface circuits. It delivers 300 mA continuous output current per channel, supports 100 V typical output breakdown voltage, features diode-clamped TTL/MOS-compatible inputs, and operates across 0°C to 70°C - commonly used in relay, solenoid, and hammer-driver control systems.
For engineers reviewing the SN75477DE4G4 datasheet, SN75477DE4G4 pinout, SN75477DE4G4 application, or SN75477DE4G4 equivalent, key selection criteria include its dual-NAND logic function, 5 V nominal supply operation, output clamp diode protection (70 V, 300 mA), pnp input stage for low input current, and SOIC-8 package compatibility with industrial-level thermal dissipation (464 mW at 70°C).
Technical Context
The SN75477DE4G4 implements two independent NAND-gated peripheral drivers with pnp transistor inputs that reduce high-level input current to ≤10 µA and low-level input current to –220 µA (S input). Each channel integrates output clamp diodes rated for 300 mA transient suppression at 70 V, enabling direct drive of inductive loads without external flyback components.
Its logic behavior follows positive-logic NAND: Y = A·S̅, with propagation delays of 200–350 ns and transition times under 125 ns at 5 V/25°C. The device is characterized for latch-up immunity up to 55 V after conducting 300 mA, and operates within strict absolute maximum ratings including 5.5 V input voltage and 400 mA continuous output current.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Logic Function | Dual independent NAND gate driver - enables active-low enable control of two separate high-side loads. |
| Output Current | 300 mA continuous per channel - sufficient to directly drive relays, small solenoids, and printer hammers. |
| Output Breakdown | 100 V typical - allows safe operation with inductive kickback from 48 V or higher DC loads. |
| Input Compatibility | TTL- and MOS-compatible with diode clamping - accepts standard 5 V logic levels without external level-shifting. |
| Supply Voltage | 4.5 V to 5.5 V - tightly regulated 5 V system integration with 725 mW max power at 25°C ambient. |
| Operating Temp | 0°C to 70°C - commercial-grade rating suitable for office equipment, point-of-sale terminals, and industrial controllers. |
| Propagation Delay | 200–350 ns - ensures deterministic timing in medium-speed electromechanical sequencing applications. |
Pinout & Package
SN75477DE4G4 is housed in an 8-pin SOIC (D) package with 1.27 mm lead pitch, 3.9 mm body width, and 1.75 mm max height - optimized for surface-mount assembly and thermal performance in compact PCB layouts.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (1A) | Input A for Channel 1 | NAND input - high-active logic input referenced to GND; pnp-driven for low input current. |
| 2 (1Y) | Output Y for Channel 1 | Open-collector high-voltage output - sinks up to 300 mA; internally clamped to 70 V. |
| 3 (GND) | Ground Reference | Power and signal return path - must be low-impedance to sustain clamp diode effectiveness. |
| 4 (CLAMP) | Common Clamp Node | Shared cathode connection for both output clamp diodes - ties to external 70 V+ supply for transient suppression. |
| 5 (VCC) | Positive Supply | +5 V DC supply input - powers internal logic and output stages; decoupling capacitor required. |
| 6 (2A) | Input A for Channel 2 | Second NAND input - electrically identical to Pin 1; supports independent dual-load control. |
| 7 (2Y) | Output Y for Channel 2 | Second open-collector output - fully isolated from Channel 1 except shared CLAMP and VCC/GND. |
| 8 (S) | Enable Input (Shared) | Active-high enable for both channels - when high, outputs respond to A inputs; when low, both outputs are high-impedance. |
Key Features
| Feature | Design Value |
|---|---|
| No latch-up at 55 V | Guarantees robust operation during inductive turn-off transients without destructive failure. |
| Diode-clamped inputs | Enables direct interfacing with 5 V TTL or CMOS logic while preventing input overvoltage damage. |
| pnp input structure | Reduces high-level input current to ≤10 µA - minimizes loading on upstream logic drivers. |
| Integrated output clamp diodes | Eliminates need for external flyback diodes when driving relays or solenoids up to 300 mA. |
| Plastic SOIC thermal design | Delivers 464 mW power dissipation at 70°C - supports sustained operation in enclosed industrial enclosures. |
Applications
| Printer Hammer Control | Relay Driver Interface |
|---|---|
Use Scenario: Driving electromagnetic print hammers in dot-matrix printers requiring precise timing and high peak current. IC Role / Device Role / Timing Role: Dual-NAND peripheral driver providing synchronized, current-limited hammer actuation with transient suppression. Use Value: Enables direct microcontroller-to-hammer interface without discrete transistors or flyback diodes, reducing BOM count by ≥4 components per channel. | Use Scenario: Controlling multiple 24 VDC industrial relays from a single 5 V logic controller. IC Role / Device Role / Timing Role: High-voltage, high-current switch with integrated clamp diodes protecting against inductive kickback. Use Value: Supports 300 mA per relay coil at up to 100 V breakdown - eliminates risk of MOSFET or BJT failure due to voltage overshoot. |
| Solenoid Sequencing System | Legacy Equipment Interface |
Use Scenario: Actuating pneumatic solenoid valves in vending machines or HVAC controls using 5 V logic signals. IC Role / Device Role / Timing Role: Dual-channel load switch with shared enable (S pin) for coordinated valve timing and power gating. Use Value: Shared S-input allows simultaneous channel disable - critical for safety-critical de-energization sequences in industrial systems. | Use Scenario: Retrofitting modern microcontrollers into aging test equipment originally designed for 74-series TTL drivers. IC Role / Device Role / Timing Role: Pin-compatible replacement for obsolete SN75477P with identical logic function and electrical behavior. Use Value: Maintains legacy timing margins (200–350 ns delay) and voltage thresholds while enabling RoHS-compliant surface-mount assembly. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual-NAND peripheral driver applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SN75477DR | Same die, tape-and-reel packaging (2500 pcs/reel) vs. tube (75 pcs); identical SOIC-8 footprint and electrical specs. | Optimized for high-volume automated assembly; same thermal and timing performance as SN75477DE4G4. | Select SN75477DR for production runs >500 units where pick-and-place efficiency matters. |
| ULN2003A | Seven Darlington drivers with built-in clamp diodes; open-collector outputs but no logic gating (inverting only); 500 mA rating. | Higher channel count but lacks NAND logic - requires external gates for enable-controlled dual-output sequencing. | Choose ULN2003A only when needing ≥3 channels or higher current; not a functional substitute for NAND logic requirement. |
Compared with SN75477DE4G4, SN75477DR offers identical functionality in volume-friendly packaging, while ULN2003A provides more outputs and current but requires external logic to replicate NAND-based enable control - making SN75477DE4G4 the only direct solution for dual-channel, logic-gated peripheral driving.
Availability
SN75477DE4G4 is available at Aetrix Electronics and suitable for printer hammer control, relay interface, solenoid sequencing, and legacy equipment retrofit applications requiring stable component supply and long-term industrial availability.
Supply support for SN75477DE4G4 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 U.S.-based semiconductor company founded in 1930, specializing in analog, embedded processing, and logic solutions for industrial, automotive, and communications markets.
The SN75477DE4G4 belongs to TI's legacy peripheral driver family, engineered specifically for robust electromechanical interface applications where high-voltage isolation, inductive load handling, and logic-level compatibility are essential.
FAQ
What logic function does the SN75477DE4G4 implement?
The SN75477DE4G4 implements two independent NAND gate drivers. Its truth table shows Y = A·S̅: when the shared enable input (Pin 8, S) is high, each output (1Y, 2Y) is the NAND of its respective input (1A, 2A) and S; when S is low, both outputs remain high-impedance. This behavior is confirmed in the official SLRS025A datasheet function tables and logic diagrams for SN75477.
Does the SN75477DE4G4 require external flyback diodes when driving relays?
No, the SN75477DE4G4 does not require external flyback diodes. It integrates internal output clamp diodes rated for 300 mA and 70 V reverse voltage, explicitly designed for inductive transient suppression. These diodes connect to the CLAMP pin (Pin 4), which must be tied to a supply ≥70 V to absorb energy from relay coils or solenoids - eliminating external components per channel.
What is the maximum continuous output current rating for the SN75477DE4G4?
The SN75477DE4G4 is characterized for 300 mA continuous output current per channel under recommended operating conditions (VCC = 4.5–5.5 V, TA = 0°C to 70°C). Absolute maximum rating allows 400 mA continuous, but datasheet specifications and thermal derating (464 mW at 70°C) confirm 300 mA as the validated, reliable operational limit for sustained use.
Is the SN75477DE4G4 pin-compatible with the through-hole SN75477P variant?
Yes, the SN75477DE4G4 (SOIC-8) and SN75477P (PDIP-8) share identical pin numbering, logic function, and electrical specifications - differing only in package type and thermal characteristics. Both use the same 8-pin layout with Pin 1 (1A), Pin 2 (1Y), Pin 3 (GND), Pin 4 (CLAMP), Pin 5 (VCC), Pin 6 (2A), Pin 7 (2Y), and Pin 8 (S), enabling direct PCB footprint substitution where board space and reflow capability permit.
What is the purpose of the CLAMP pin (Pin 4) on the SN75477DE4G4?
The CLAMP pin (Pin 4) on the SN75477DE4G4 serves as the common cathode node for both internal output clamp diodes. It must be connected to a voltage rail ≥70 V (e.g., +72 V or +100 V) to provide a safe path for inductive kickback energy when driving relays or solenoids. Without this external high-voltage connection, the clamp diodes cannot suppress transients - rendering the protection ineffective and risking output stage damage.
SN75477DE4G4 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- *
- Package/Case:
- -
- Packaging:
- Bulk
- Product Status:
- Active
- Logic Type:
- -
- Number of Elements:
- -
- Number of Bits per Element:
- -
- Input Type:
- -
- Output Type:
- -
- Current - Output High, Low:
- -
- Voltage - Supply:
- -
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- -
- Supplier Device Package:
- -
SN75477DE4G4 FAQ
1.How can I place an order for SN75477DE4G4 through Aetrix?
Please submit a Request for Quotation (RFQ) for SN75477DE4G4 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 SN75477DE4G4 reliable?
The price and inventory of SN75477DE4G4 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SN75477DE4G4 is usually 5 days.
3.What payment methods are accepted for SN75477DE4G4?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SN75477DE4G4 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SN75477DE4G4?
SN75477DE4G4 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SN75477DE4G4 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 SN75477DE4G4?
For technical support, including SN75477DE4G4 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SN75477DE4G4 requirements.
6.How does Aetrix verify that SN75477DE4G4 is sourced from the original manufacturer or authorized distributors?
All SN75477DE4G4 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 SN75477DE4G4 meets industry standards.
7.What is the process for return or replacement of SN75477DE4G4?
All SN75477DE4G4 units undergo pre-shipment inspection (PSI). If there is an issue with SN75477DE4G4, 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 SN75477DE4G4 part is unused and in its original packaging.
Return procedure for SN75477DE4G4:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SN75477DE4G4 Tags
-
SN74LVC1G17DBVR
Texas Instruments
-
SN74LVC1G07DCKR
Texas Instruments
-
SN74LVC1G17DCKR
Texas Instruments
-
SN74LVC1G07DBVR
Texas Instruments
-
SN74LVC1G125DCKR
Texas Instruments
-
SN74AHCT1G126DBVR
Texas Instruments
-
SN74LVC1G125DBVR
Texas Instruments
-
SN74AHCT1G125DBVR
Texas Instruments
-
SN74LVC2G17DBVR
Texas Instruments
-
SN74LVC2G07DCKR
Texas Instruments
-
SN74LVC1G34DCKR
Texas Instruments
-
SN74LVC2G17DCKR
Texas Instruments
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…
