TL594INSR - 40V 0.2A 300kHz PWM Controller | Texas Instruments
MPN: TL594INSR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.85 | $1.85 |
| 10 | $1.62 | $16.20 |
| 100 | $1.38 | $138.00 |
| 500 | $1.15 | $575.00 |
| 1,000 | $0.97 | $970.00 |
TL594INSR Overview
What is a PWM controller? A PWM controller is a power-management integrated circuit that generates switching signals whose duty cycle is modulated to regulate voltage or current in switching power supplies. The TL594 belongs to the voltage-mode PWM controller category, which sits in the hierarchy of PWM controller -> switching controller -> DC-DC controller -> power management IC -> semiconductor. Voltage-mode controllers regulate by comparing an error-amplifier output to a sawtooth waveform, making them robust, well-understood, and tolerant of noisy measurement environments.
The TL594INSR supports buck, boost, flyback, forward, full-bridge, half-bridge, and push-pull topologies, giving designers a single IC for multiple converter architectures. Key features include 5 V (±5%) internal reference output, programmable dead-time control (DTC), programmable oscillator frequency up to 300 kHz via external RT and CT, and uncommitted 200 mA open-collector outputs that can be configured in common-emitter or emitter-follower mode for either single-ended or push-pull operation.
At the architecture level, the TL594 uses a bandgap-derived 5 V reference feeding two identical error amplifiers with uncommitted inputs and outputs, allowing flexible feedback loop design. The oscillator section generates a sawtooth whose rise time is set by RT-CT and whose maximum frequency is 300 kHz, with internal circuitry that prevents simultaneous conduction of the output stages during transitions (dead-time control). Protection features include UVLO with typical 6 V turn-on threshold and thermal considerations for the SOP-16 (NS) thermal pad.
Typical applications include DC-DC converters in industrial power systems, SMPS for telecom and networking equipment, battery chargers using buck or boost topologies, and motor-drive forward converters. Designers favor the TL594 for its topology flexibility and proven architecture in long-lifecycle designs.
When designing with this part, ensure RT and CT values are selected to keep oscillator frequency below 300 kHz under all temperature and tolerance conditions, and add adequate bulk capacitance on VCC to prevent UVLO retriggering during start-up.
Drop-in alternatives for TL594INSR — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
TL594CNSR
✅ Drop-In📋 Reference alternative (not in catalog)
TL594IDR
✅ Drop-In📋 Reference alternative (not in catalog)
TL594CNSRG4
✅ Drop-In📋 Reference alternative (not in catalog)
TL594INSR Maximum Ratings & Electrical Characteristics
| Topology | Buck, Boost, Flyback, Forward, Full-Bridge, Half-Bridge, Push-Pull |
| PWM Control Method | Voltage Mode |
| Maximum Supply Voltage | 40 V |
| Output Current (per output) | 200 mA |
| Maximum Switching Frequency | 300 kHz |
| Reference Voltage | 5 V ±5% |
| Output Type | Transistor Driver (uncommitted, sink/source) |
| Dead-Time Control | Yes (programmable via DTC pin) |
| Undervoltage Lockout (UVLO) | Yes (integrated) |
| Number of Error Amplifiers | 2 (uncommitted inputs/outputs) |
| Maximum Duty Cycle | 45% |
| Operating Temperature Range | -40 °C to +85 °C |
| Package | 16-Pin SOIC (NS), Tape and Reel |
| Pin Count | 16 |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
TL594INSR Pin Configuration
| Pin 1 | 1IN+ — Error amplifier 1 non-inverting input |
| Pin 2 | 1IN- — Error amplifier 1 inverting input |
| Pin 3 | FEEDBACK — Feedback pin (error amp output / PWM comparator input) |
| Pin 4 | DTC — Dead-time control input |
| Pin 5 | CT — Oscillator timing capacitor |
| Pin 6 | RT — Oscillator timing resistor |
| Pin 7 | GND — Ground |
| Pin 8 | C1 — Output transistor 1 collector |
| Pin 9 | E1 — Output transistor 1 emitter |
| Pin 10 | E2 — Output transistor 2 emitter |
| Pin 11 | C2 — Output transistor 2 collector |
| Pin 12 | VCC — Supply voltage (7 V to 40 V) |
| Pin 13 | OUTPUT CTRL — Output mode control (push-pull vs single-ended) |
| Pin 14 | REF — 5 V reference output |
| Pin 15 | 2IN- — Error amplifier 2 inverting input |
| Pin 16 | 2IN+ — Error amplifier 2 non-inverting input |
Typical Applications
TL594INSR is suitable for 6 applications: Industrial SMPS Power Supply, DC-DC Buck Converter, Forward Converter Power Stage, Push-Pull Converter, Battery Charger (Boost Topology), Half-Bridge / Full-Bridge Converter.
Industrial SMPS Power Supply
The TL594INSR's 40 V max VCC and 200 mA output drive suit it for industrial switch-mode power supplies (SMPS) driving MOSFET half-bridge or push-pull stages. Its voltage-mode PWM control with programmable dead-time prevents shoot-through in half-bridge converters. The integrated UVLO (6 V typical) protects the converter from unstable startup at low line conditions, while the 5 V internal reference provides a stable bias for optocoupler feedback loops. Two uncommitted error amplifiers support primary-side voltage regulation and secondary-side current limiting, making it well-suited for 50 W to 500 W industrial PSU designs.
Recommended
DC-DC Buck Converter
For buck topology applications, the TL594INSR can drive a high-side P-channel MOSFET or low-side N-channel MOSFET through its 200 mA uncommitted outputs. The programmable dead-time control (DTC) pin eliminates cross-conduction losses during switching transitions, improving efficiency at high switching frequencies up to 300 kHz. The two error amplifiers allow voltage-mode control with feedforward line regulation. Buck designs using TL594INSR are common in 24 V industrial bus to 5 V/3.3 V logic conversion where the 40 V max VCC provides adequate headroom for transients on the 24 V input.
Recommended
Forward Converter Power Stage
The TL594INSR is a classic forward-converter controller where its push-pull output stage directly drives the primary-side MOSFET through a gate-drive transformer. The 200 mA sink-source capability is sufficient to drive most medium-power MOSFETs without external drivers. Integrated UVLO ensures clean startup from rectified bulk capacitor voltages, while the 45% maximum duty cycle prevents transformer saturation in single-switch forward topologies. Forward converters using TL594INSR are common in 100 W telecom and industrial isolated DC-DC applications.
Recommended
Push-Pull Converter
For push-pull topology, the TL594INSR's two output stages (C1/E1 and C2/E2) directly drive the two primary-side MOSFETs or through a gate-drive transformer. The internal dead-time logic prevents simultaneous turn-on, which would cause transformer saturation. Maximum duty cycle of 45% per output (90% combined) leaves margin for transformer reset in push-pull designs. This topology is widely used in low-voltage isolated DC-DC modules where galvanic isolation is required between input and output rails.
Recommended
Battery Charger (Boost Topology)
For battery chargers using boost topology, the TL594INSR drives the boost MOSFET with its 200 mA output while the voltage-mode control loop regulates battery charging current or voltage. The 5 V internal reference provides stable bias for current-sense amplifier feedback. Programmable oscillator up to 300 kHz enables compact magnetics in portable charger designs. Boost chargers using TL594INSR are common in lead-acid battery backup systems where the 40 V VCC range supports 12 V and 24 V battery stacks.
Recommended
Half-Bridge / Full-Bridge Converter
For half-bridge and full-bridge topologies, the TL594INSR's programmable dead-time control (DTC) is critical to prevent shoot-through between the high-side and low-side MOSFETs. The two 200 mA outputs can drive gate-drive transformers in bridge configurations, or low-side MOSFETs directly when using bootstrap drivers. The 45% maximum duty cycle per output fits half-bridge transformer flux-balance requirements. Full-bridge applications using TL594INSR are common in 500 W to 2 kW telecom rectifier and welding-inverter designs.
Recommended
Recommended Products Summary
Engineering reference data for TL594INSR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | TL594CNSR | TL594IDR | TL594CNSRG4 |
|---|---|---|---|---|
| Package | SOIC-16 (NS) | SOIC-16 (NS) - same | SOIC-16 (NS) - same | SOIC-16 (NS) - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Max Supply Voltage | 40 V | 40 V | 40 V | 40 V |
| Output Current | 200 mA | 200 mA | 200 mA | 200 mA |
| Max Frequency | 300 kHz | 300 kHz | 300 kHz | 300 kHz |
| Operating Temperature | -40 °C to +85 °C (Industrial) | 0 °C to +70 °C (Commercial) | -40 °C to +85 °C (Automotive) | 0 °C to +70 °C (Commercial) |
| AEC-Q100 Qualified | No | No | Yes | No |
| Lead-Free | Yes | Yes | Yes | Yes (G4 suffix) |
Key Differentiators
- Industrial temperature range with full -40 °C to +85 °C operation (vs TL594CNSR)
- Standard industrial grade (no automotive surcharge) (vs TL594IDR)
- Integrated UVLO protection (vs TL494 family)
Design Notes
Ensure VCC bulk capacitance is sized to hold VCC above the UVLO threshold (typically 6 V) during startup until the auxiliary winding powers the IC. Insufficient bulk capacitance causes UVLO retriggering and converter startup failure. Add at least 10 µF low-ESR capacitance on VCC for typical 12 V to 24 V input designs.
Route RT, CT, and DTC traces away from the switching power stage to prevent noise injection into the oscillator. Keep ground return paths short and use a single-point ground connection at the TL594INSR GND pin (pin 7) to avoid ground bounce in the oscillator section. Place RT and CT components close to pins 5 and 6 to minimize parasitic capacitance.
When configuring outputs in emitter-follower mode (OUTPUT CTRL pin tied to VCC), each output transistor can only source current and cannot sink. For topologies requiring sink current (e.g., low-side N-MOSFET drive), use common-emitter mode (OUTPUT CTRL tied to GND). Mismatched configuration is a common cause of MOSFET drive failure.
Compliance Information
RoHS and REACH compliant per TI product page. Not AEC-Q100 qualified - choose TL594IDR for automotive applications. Halogen-free per TI packaging materials disclosure.
