My Inquiry
My Account
Texas Instruments TL497ACN
- Part No.:
- TL497ACN
- Manufacturer:
- Texas Instruments
- Package:
- 14-DIP (0.300", 7.62mm)
- Datasheet:
-
TL497ACN.pdf
- Description:
- IC REG BUCK BST ADJ 500MA 14PDIP
- Quantity:
- Payment:
- Shipping:
Inventory:287
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
TL497ACN from Texas Instruments is a fixed-on-time, variable-frequency switching voltage regulator controller IC designed for buck, boost, and inverting DC-DC conversion. It integrates an internal 500 mA NPN power switch, 1.2 V reference, current-limit sensing, TTL-compatible inhibit, and soft-start capability. It operates from 4.5 V to 12 V input and delivers stable output voltage with 0.4% typical regulation-used in portable instrumentation power supplies requiring high efficiency (>60%) and minimal external components.
For engineers reviewing the TL497ACN datasheet, TL497ACN pinout, TL497ACN application, or TL497ACN equivalent, this page provides verified functional identity, validated 14-pin PDIP package mapping, confirmed operating temperature range (0°C to 70°C), real-world configuration flexibility (buck/boost/invert), and direct alternative part comparisons grounded in TI's official documentation and ordering data.
Technical Context
The TL497ACN implements a constant-on-time oscillator whose timing capacitor (CT) sets switch-on duration independent of input voltage-enabled by internal proportional current and threshold scaling with VCC. Its comparator compares feedback voltage against a 1.2 V substrate-referenced reference to regulate output via duty-cycle modulation.
Internal protection includes adjustable peak-current limiting (triggered at 0.7 V across RCL), TTL-compatible inhibit gating, and integrated Schottky diode for commutation. The uncommitted collector/emitter allows flexible topology implementation, while base/base drive pins are reserved for test only and unused in circuit design.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Supply Voltage Range | 4.5 V to 12 V - defines minimum startup voltage and maximum safe operating rail for internal circuitry and switch driver. |
| Peak Switch Current | 500 mA - maximum continuous inductive peak current supported by internal NPN transistor without external boost. |
| Reference Voltage | 1.2 V (substrate-referenced) - precision feedback threshold enabling accurate output voltage setting via R1/R2 divider. |
| Input Regulation | 0.2% typical - indicates load-independent stability against input voltage variation within operating range. |
| Output Regulation | 0.4% typical - quantifies output voltage deviation under changing load conditions at fixed input. |
| Operating Temperature | 0°C to 70°C - commercial-grade thermal envelope validated for TL497ACN variant per TI's characterization. |
| Switch On-State Voltage | 0.85 V max at 500 mA - determines conduction loss and thermal rise in internal pass transistor during active phase. |
Pinout & Package
TL497ACN is supplied in a 14-pin Plastic Dual-In-Line Package (PDIP-N), with 0.3-inch body width, through-hole mounting, and standard DIP lead pitch (0.1 inch). Thermal impedance θJA = 101°C/W enables moderate-power operation without forced cooling in ambient conditions.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (COMP INPUT) | Feedback comparator input | Accepts resistor-divider voltage from output; compared to 1.2 V reference to initiate switching cycle when below threshold. |
| 2 (INHIBIT) | Digital enable/disable control | TTL-compatible logic input; high level disables oscillator and internal switch, forcing output shutdown. |
| 3 (FREQ CONTROL) | Oscillator timing node | Connects external CT capacitor; internal constant-current source charges CT to set fixed on-time (e.g., 22 µs with 250 pF). |
| 4 (SUBSTRATE) | Reference potential | Substrate connection point; serves as reference for 1.2 V comparator and must be tied to system ground or lowest potential node. |
| 5 (GND) | Power ground | Main return path for internal bias currents and switch emitter current; separate from SUBSTRATE but typically connected. |
| 6 (CATHODE) | Integrated Schottky cathode | Connected internally to collector; used in boost/invert topologies for freewheeling path or blocking function. |
| 7 (ANODE) | Integrated Schottky anode | Internally tied to emitter; completes diode path with CATHODE for synchronous rectification or flyback clamping. |
| 8 (VCC) | Positive supply input | Primary power rail (4.5–12 V); powers internal logic, oscillator, and base drive; also feeds current-limit sense network. |
| 9 (CUR LIM SENS) | Current limit threshold input | Monitors voltage drop across external RCL; triggers current-limit circuit when ≥0.7 V is detected. |
| 10 (BASE DRIVE) | Test-only base drive signal | Factory test pin only; no functional role in application circuits; must be left unconnected. |
| 11 (BASE) | Test-only base connection | Factory test pin only; no functional role in application circuits; must be left unconnected. |
| 12 (COL OUT) | Internal NPN collector output | High-side switching node; connects to inductor in boost, to input in buck, or to ground in inverting configurations. |
| 13 (NC) | No internal connection | Unbonded pin; electrically isolated; may be left floating or grounded for mechanical stability. |
| 14 (EMIT OUT) | Internal NPN emitter output | Low-side switching node; referenced to GND/SUBSTRATE; forms switch leg with COL OUT for topology flexibility. |
Key Features
| Feature | Design Value |
|---|---|
| Buck/Boost/Inverting Configurability | Single IC supports all three fundamental DC-DC topologies using same pinout and external component set-reduces BOM count and design reuse effort. |
| Adjustable Output Voltage | Set precisely via external R1/R2 resistor divider referenced to 1.2 V internal reference-enables custom output from 1.2 V up to 30 V (step-up) or −25 V (inverting). |
| Soft Start-Up Capability | Gradual output ramp enabled by controlled CT charging-prevents inrush current and stabilizes startup in sensitive analog or microcontroller systems. |
| Input Current Limit Protection | Programmable peak-current limit via RCL resistor (0.7 V threshold)-protects inductor from saturation and internal transistor from overstress during fault or overload. |
| TTL-Compatible Inhibit | Digital ON/OFF control with 2.5 V VIH min and 0.8 V VIL max-allows direct interfacing with microcontrollers, FPGAs, or logic sequencers without level-shifting. |
Applications
| Portable Medical Sensors | Industrial Data Acquisition |
|---|---|
Use Scenario: Powering low-noise analog front-ends in handheld ECG or pulse oximetry units where battery life and compact size are critical. IC Role / Device Role / Timing Role: TL497ACN acts as the primary DC-DC converter generating regulated ±5 V rails from a single 9 V alkaline cell, using inverting and step-down configurations. Use Value: Achieves >60% efficiency at light loads and maintains 0.4% output regulation despite battery voltage decay from 9 V to 6 V. |
Use Scenario: Supplying isolated ADC reference and op-amp bias rails in modular PLC I/O modules operating from 24 V industrial bus. IC Role / Device Role / Timing Role: TL497ACN functions as a local step-down regulator delivering 5 V to mixed-signal circuitry, with INHIBIT synchronized to system sleep mode. Use Value: Soft start prevents digital noise coupling into precision analog sections during power-up; TTL inhibit enables zero-quiescent-current standby. |
| Automotive Aftermarket Telematics | Test & Measurement Equipment |
Use Scenario: Generating stable 3.3 V and −12 V rails for GPS/GSM modules and RF front-ends in vehicle-mounted fleet trackers. IC Role / Device Role / Timing Role: TL497ACN implements dual-output regulation: step-down for 3.3 V logic and inverting for −12 V op-amp bias, sharing one inductor and CT capacitor. Use Value: Fixed-on-time architecture ensures consistent transient response across 9–16 V automotive input range; integrated Schottky reduces external part count. |
Use Scenario: Providing programmable auxiliary supplies in benchtop multimeters and oscilloscope channel amplifiers requiring clean, low-drift bias voltages. IC Role / Device Role / Timing Role: TL497ACN serves as a user-adjustable lab supply core, with R1/R2 potentiometer enabling fine-tuned output from 1.2 V to 15 V. Use Value: 0.2% input regulation and 1.2 V reference accuracy support <10 ppm/V line regulation-critical for metrology-grade calibration paths. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar switching regulator controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LM2577-ADJ | Fixed-frequency PWM (52 kHz), higher peak current (3 A), no integrated Schottky, requires external diode. | Better suited for high-current step-up applications (>1 A); lacks inverting capability and substrate-referenced reference. | Select LM2577-ADJ when higher output current or fixed-frequency EMI control is required; TL497ACN preferred for multi-topology flexibility and lower component count. |
| MC34063AP | Fixed-frequency (100 kHz), 1.5 A switch, no soft start, wider VCC range (3–40 V), no integrated diode. | More robust for wide-input industrial supplies; lacks TTL inhibit and precise 1.2 V reference-requires external reference for tight regulation. | Choose MC34063AP for cost-sensitive, high-input-voltage designs; TL497ACN offers superior regulation accuracy and built-in protection features at moderate current levels. |
Compared with LM2577-ADJ and MC34063AP, the TL497ACN delivers unique value in topology versatility (buck/boost/invert), integrated Schottky diode, and substrate-referenced 1.2 V reference-making it optimal for compact, multi-rail, low-to-moderate power systems where regulation precision and design simplicity outweigh raw current capability.
Availability
TL497ACN is available at Aetrix Electronics and suitable for portable medical sensors, industrial data acquisition modules, automotive telematics, test equipment, and embedded power management requiring stable component supply across commercial temperature range.
Supply support for TL497ACN 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 power management technologies, with over 50 years of innovation in high-reliability analog ICs.
The TL497A product line was developed as a monolithic switching regulator controller family to simplify discrete DC-DC design-targeting cost-sensitive, space-constrained applications in instrumentation, industrial controls, and portable electronics.
FAQ
What is the maximum output voltage achievable with TL497ACN in boost configuration?
The TL497ACN supports up to 30 V output in step-up configuration per TI's recommended operating conditions. This limit arises from the absolute maximum output voltage rating of 35 V and practical constraints of external component selection-including inductor saturation current, diode reverse voltage, and capacitor voltage rating. Design equations in the datasheet confirm VO ≤ VI + 2 V for reliable operation, making 30 V achievable from a 12 V input with appropriate layout and component derating.
Does TL497ACN require an external catch diode in inverting configuration?
Yes, TL497ACN requires an external catch diode (e.g., 1N4001) in inverting configuration, as explicitly stated in Figure 3 of the datasheet. Although TL497ACN includes an integrated Schottky diode between CATHODE and ANODE, its internal diode is optimized for commutation in boost and buck modes-not for the polarity reversal needed in inverting topologies. Using the internal diode alone would result in incorrect current path and failure to regulate negative output.
Can TL497ACN operate with input voltage below 4.5 V?
No, TL497ACN is not characterized or guaranteed to operate reliably below 4.5 V. The recommended operating condition specifies a minimum VCC of 4.5 V, and electrical characteristics-including reference voltage accuracy, switch on-state voltage, and oscillator timing-are only validated within 4.5 V to 12 V. Operation below 4.5 V may cause erratic switching, failure to start, or degraded regulation; for sub-4.5 V inputs, consider TI's TPS610xx or MAXIM's MAX1771 alternatives.
What is the purpose of the NC pin (Pin 13) on TL497ACN?
Pin 13 on TL497ACN is designated NC (No internal connection) per TI's official pinout diagram and package drawing. It is physically present but electrically unconnected to any internal circuitry. While it may be grounded for mechanical stability or left floating, it contributes no functional behavior-unlike BASE (Pin 11) and BASE DRIVE (Pin 10), which are test-only and must remain unconnected in application circuits.
How does the TL497ACN's fixed-on-time architecture improve regulation under varying input conditions?
TL497ACN's fixed-on-time architecture improves regulation by decoupling switch conduction time from input voltage: the internal CT charging current and threshold scale proportionally with VCC, maintaining constant on-time across 4.5–12 V. This results in automatic frequency adjustment-higher input yields shorter off-time and higher frequency-which preserves loop stability and minimizes output ripple during line transients, unlike fixed-frequency controllers that require complex compensation networks.
TL497ACN Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 14-DIP (0.300", 7.62mm)
- Packaging:
- Bulk
- Product Status:
- Active
- Function:
- Step-Up, Step-Down
- Output Configuration:
- Positive or Negative
- Topology:
- Buck, Boost
- Output Type:
- Adjustable
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 4.5V
- Voltage - Input (Max):
- 12V
- Voltage - Output (Min/Fixed):
- ±1.2V
- Voltage - Output (Max):
- 30V, -25V
- Current - Output:
- 500mA (Switch)
- Frequency - Switching:
- -
- Synchronous Rectifier:
- No
- Operating Temperature:
- 0°C ~ 70°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- 14-PDIP
TL497ACN FAQ
1.How can I place an order for TL497ACN through Aetrix?
Please submit a Request for Quotation (RFQ) for TL497ACN 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 TL497ACN reliable?
The price and inventory of TL497ACN are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for TL497ACN is usually 5 days.
3.What payment methods are accepted for TL497ACN?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for TL497ACN transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for TL497ACN?
TL497ACN orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your TL497ACN 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 TL497ACN?
For technical support, including TL497ACN datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your TL497ACN requirements.
6.How does Aetrix verify that TL497ACN is sourced from the original manufacturer or authorized distributors?
All TL497ACN 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 TL497ACN meets industry standards.
7.What is the process for return or replacement of TL497ACN?
All TL497ACN units undergo pre-shipment inspection (PSI). If there is an issue with TL497ACN, 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 TL497ACN part is unused and in its original packaging.
Return procedure for TL497ACN:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
TL497ACN Tags
-
TPS562201DDCR
Texas Instruments
-
MC34063ABD-TR
STMicroelectronics
-
TPS561201DDCR
Texas Instruments
-
MC33063ADR
Texas Instruments
-
MC34063ADR
Texas Instruments
-
TPS560200DBVR
Texas Instruments
-
AP3012KTR-G1
Diodes Incorporated
-
TLV61048DBVR
Texas Instruments
-
AZ34063UMTR-G1
Diodes Incorporated
-
TPS562200DDCR
Texas Instruments
-
AP62300TWU-7
Diodes Incorporated
-
MC34063EBD-TR
STMicroelectronics
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…
