NJM7915FA - -15V 1.5A Negative LDO Regulator TO-220F | NJR
MPN: NJM7915FA ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.1 | $1.10 |
| 10 | $0.95 | $9.50 |
| 100 | $0.78 | $78.00 |
| 500 | $0.65 | $325.00 |
| 1,000 | $0.5 | $500.00 |
NJM7915FA Overview
A negative linear regulator (also called a negative LDO or negative 3-terminal regulator) is a type of voltage regulator that produces a stable negative output voltage relative to ground from a more-negative input rail. In the power-management IC hierarchy, the NJM7915FA sits below adjustable switching controllers and above simple Zener shunts, occupying the same product category as the LM7905, LM7912, and LM7915 from Texas Instruments. The device replaces discrete resistor-Zener or op-amp-based negative references with a single drop-in IC, saving PCB area and improving temperature coefficient. Because output polarity is fixed at -15 V, the regulator is commonly paired with a +15 V (NJM7815FA) device to create ±15 V analog supplies.
The most important feature of the NJM7915FA is its high 1.5 A output current in a TO-220F isolated package, which allows direct mounting to a heatsink without an insulating washer when the tab is internally isolated. Additional features include internal short-circuit current limiting, thermal shutdown at approximately 150 °C junction, low quiescent current compared to older LM79xx designs, and excellent ripple rejection because the part uses the same bandgap reference architecture as NJR's 78xx series. The TO-220F (FA suffix) variant provides full isolation between the metal tab and the die, simplifying mechanical assembly and reducing the risk of tab-to-ground shorts during production.
In application, the NJM7915FA is typically placed after a transformer-rectifier-capacitor bulk filter and provides a regulated -15 V rail for op-amps, DACs, ADCs, instrumentation amplifiers, and audio preamplifiers. Designers should add a 0.33 µF input capacitor and a 0.1 µF output capacitor (tantalum or low-ESR ceramic) close to the IC, plus adequate heatsinking when VIN-VOUT differential exceeds 5 V at high load. As of 2026-10-09 distributor pricing puts the part at roughly $0.75-$1.20 in 1-piece quantity and under $0.50 at 1k reels.
Designers should consider the power dissipation budget carefully: at 1.5 A load with VIN = -20 V and VOUT = -15 V, dissipation is 7.5 W and a heatsink is mandatory. The isolated TO-220F tab allows direct mounting to a grounded chassis without an insulating pad.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet. Engineers comparing the NJM7915FA to cross-brand 7915 regulators will find a side-by-side parametric comparison below.
Drop-in alternatives for NJM7915FA — 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:
NJM7915FA-#ZZZB
✅ Drop-In📋 Reference alternative (not in catalog)
LM7915CT
✅ Drop-In📋 Reference alternative (not in catalog)
MC7915CTG
✅ Drop-In📋 Reference alternative (not in catalog)
L7915CV
✅ Drop-In📋 Reference alternative (not in catalog)
MC7915BTG
✅ Drop-In📋 Reference alternative (not in catalog)
LM7915CT/NOPB
✅ Drop-In📋 Reference alternative (not in catalog)
NJM7915FA Maximum Ratings & Electrical Characteristics
| Manufacturer | NJR (Nisshinbo Micro Devices / New Japan Radio) |
| Product Category | Linear Regulators - Standard |
| Regulator Topology | Negative 3-Terminal Linear Regulator |
| Polarity | Negative |
| Output Type | Fixed |
| Output Voltage | -15 V |
| Output Voltage Tolerance | ±4% (typical for 79xx series) |
| Output Current | 1.5 A (continuous) |
| Input Voltage Range (max) | -35 V (absolute max) |
| Operating Temperature | -20 °C to +75 °C (NJR commercial) |
| Internal Protection | Current Limit, Thermal Shutdown |
| Package | TO-220F (3-pin + tab, isolated) |
| Mounting Type | Through-Hole |
| Pin Count | 3 (IN, COMMON, OUT) + isolated tab |
| RoHS Status | Compliant (per distributor listing) |
| Lead-Free | Yes |
| MSL Level | Not Applicable (through-hole) |
NJM7915FA Pin Configuration
| Pin 1 | COMMON — Ground reference (0 V); tied to system ground |
| Pin 2 | IN — Negative input voltage (e.g. -18 V to -24 V unregulated) |
| Pin 3 | OUT — Regulated -15 V output |
| Pin Tab | TAB (Isolated) — Mechanically attached heatsink tab; electrically isolated from die - may be grounded or floated |
Typical Applications
NJM7915FA is suitable for 6 applications: Op-Amp Negative Supply Rail, Industrial ±15 V Split Supply, Audio DAC Negative Analog Rail, Test and Measurement Instrumentation, Power Supply for Signal Relays and Solenoids, Automotive Infotainment Negative Rails.
Op-Amp Negative Supply Rail
The NJM7915FA delivers a clean -15 V rail for the V- pin of dual-supply op-amps such as the NE5532, OPA2134, or LM4562 in audio preamps and instrumentation circuits. Its 1.5 A continuous output supports multiple op-amps plus headroom, while fixed -15 V eliminates external resistor dividers and trim steps. The TO-220F isolated tab allows the heatsink to be tied directly to chassis ground without an insulating washer. Compared with a discrete Zener+pass-BJT regulator, the NJM7915FA delivers tighter line/load regulation and built-in current-limit and thermal-shutdown protection, improving long-term reliability in pro-audio and measurement equipment. Place a 0.33 µF input cap and 0.1 µF output cap within a few centimeters of the IC pins to guarantee stability.
Recommended
Industrial ±15 V Split Supply
Pair the NJM7915FA with an NJM7815FA (+15 V, 1.5 A) to build a complete ±15 V split supply for industrial instrumentation, PLC analog I/O boards, and process-control signal conditioning. Each regulator handles 1.5 A continuous and dissipates (VIN-VOUT) × IOUT of heat; at -20 V input and 1 A load, dissipation is 5 W and a small clip-on heatsink is required. The isolated TO-220F tab lets the engineer mount both regulators on a single grounded aluminum extrusion without insulating pads, simplifying the mechanical assembly. Built-in current-limit and thermal-shutdown make the supply tolerant of output shorts during board bring-up and field service, which is critical for 24/7 industrial installations.
Recommended
Audio DAC Negative Analog Rail
High-resolution audio DACs (such as the PCM1794A, ES9038Q2M, or AK4493) require a clean negative analog supply rail that matches the positive AVDD to keep common-mode voltage at midscale. The NJM7915FA's -15 V fixed output and 1.5 A capacity make it a strong choice for DAC AVDD- in audiophile DACs and headphone amplifiers. The part's high PSRR (typical of the NJM7900 planar epitaxial process) attenuates switching-converter ripple that may be present on the upstream rectified rail. For best noise performance, follow the regulator with a low-noise post-filter such as the LT3042 or TPS7A30 to drop residual ripple below 10 µVrms into the DAC reference pin.
Recommended
Test and Measurement Instrumentation
Bench instruments such as digital multimeters, oscilloscope front-ends, and arbitrary waveform generators use ±15 V split supplies to power analog input stages, ADC drivers, and output amplifiers. The NJM7915FA supplies the negative rail with 1.5 A continuous and ±4% output tolerance, sufficient for most general-purpose signal-conditioning front-ends. The device's thermal-shutdown and internal current-limit protect the instrument from accidental output shorts during calibration or user-cable faults. Designers can use the same TO-220F footprint across multiple SKUs (LM7915, L7915, MC7915) for second-source flexibility without PCB rework.
Recommended
Power Supply for Signal Relays and Solenoids
Although signal relays and small solenoids typically run from positive rails, some latching and bi-stable relays require a brief negative bias pulse to release. The NJM7915FA can source up to 1.5 A for a few hundred milliseconds to flip a 24 V-rated bi-stable relay, and its current-limit protects the IC from inductive kickback. Combined with a flyback diode across the relay coil, this gives a robust negative-pulse generator for telecom, security-panel, and instrumentation switching applications. The isolated TO-220F tab enables direct mounting to a chassis-side heatsink in rack-mounted equipment.
Recommended
Automotive Infotainment Negative Rails
Modern automotive head units and infotainment amplifiers often include analog audio blocks that need a negative rail derived from the 12 V battery. The NJM7915FA can be preceded by a switching pre-regulator that steps the 12 V battery up and inverts to -18 V, then regulated down to -15 V by the NJM7915FA for the audio op-amp section. The regulator's thermal-shutdown protects it under the harsh automotive temperature environment (-20 °C to +75 °C commercial grade or industrial-grade part for extended range). Designers should validate vibration and mechanical-shock robustness of the TO-220F through-hole lead forming in conformance with automotive QS9000 / IATF 16949 processes.
Recommended
Recommended Products Summary
Engineering reference data for NJM7915FA — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | NJM7915FA-#ZZZB | LM7915CT | MC7915CTG | L7915CV | MC7915BTG | LM7915CT/NOPB |
|---|---|---|---|---|---|---|---|
| Package | TO-220F (3-pin + isolated tab) | TO-220F (3-pin + isolated tab) - same | TO-220 (3-pin, non-isolated tab) | TO-220 (3-pin, non-isolated tab) | TO-220 (3-pin, non-isolated tab) | TO-220 (3-pin, non-isolated tab) | TO-220 (3-pin, non-isolated tab) |
| Brand | NJR (Nisshinbo) | NJR (Nisshinbo) - same | Texas Instruments | onsemi | STMicroelectronics | onsemi | Texas Instruments |
| Output Voltage | -15 V (fixed) | -15 V | -15 V | -15 V | -15 V | -15 V | -15 V |
| Output Current (max) | 1.5 A | 1.5 A | 1.5 A | 1.5 A | 1.5 A | 1.5 A | 1.5 A |
| Pinout (1/2/3) | COMMON / IN / OUT | COMMON / IN / OUT - same | COMMON / IN / OUT - same | COMMON / IN / OUT - same | COMMON / IN / OUT - same | COMMON / IN / OUT - same | COMMON / IN / OUT - same |
| Tab Connection | Isolated (electrically floating) | Isolated - same | Tied to COMMON (non-isolated) | Tied to COMMON (non-isolated) | Tied to COMMON (non-isolated) | Tied to COMMON (non-isolated) | Tied to COMMON (non-isolated) |
| Internal Protection | Current Limit + Thermal Shutdown | Current Limit + Thermal Shutdown - same | Current Limit + Thermal Shutdown - same | Current Limit + Thermal Shutdown - same | Current Limit + Thermal Shutdown - same | Current Limit + Thermal Shutdown - same | Current Limit + Thermal Shutdown - same |
| Required Input/Output Caps | 0.33 µF in / 0.1 µF out | 0.33 µF in / 0.1 µF out - same | 0.33 µF in / 0.1 µF out - same | 0.33 µF in / 0.1 µF out - same | 0.33 µF in / 0.1 µF out - same | 0.33 µF in / 0.1 µF out - same | 0.33 µF in / 0.1 µF out - same |
| Approx. Unit Price @ 1k (USD, as of 2026-10-09) | 0.50 | ~0.50 (same die) | ~0.45 | ~0.42 | ~0.48 | ~0.42 | ~0.46 |
Key Differentiators
- Isolated tab for direct heatsink mounting (vs LM7915CT (non-isolated tab))
- NJR planar epitaxial process for low noise (vs MC7915CTG)
- Wider second-source ecosystem than competing negatives (vs L7915CV)
Design Notes
Power dissipation in the NJM7915FA equals (VIN - VOUT) × IOUT. At VIN = -20 V, VOUT = -15 V, and IOUT = 1 A, dissipation is 5 W; at full 1.5 A load it rises to 7.5 W. The TO-220F package has a typical θJA of 60 °C/W when mounted on a 1 sq-in copper pad, so a 5 W dissipation produces a 300 °C junction rise above ambient - clearly beyond the 150 °C shutdown threshold. Always mount the device on a heatsink sized so that (VIN - VOUT) × IOUT × θJA(heatsink) stays below 75 °C rise.
Do NOT substitute a non-isolated TO-220 LM7915 in place of the TO-220F NJM7915FA without verifying the tab grounding scheme. The FA suffix means the tab is electrically isolated from the die; the standard TO-220 LM7915 has its tab tied to COMMON. If the heatsink is grounded and you swap in a non-isolated part, you will short COMMON to ground through the heatsink and the regulator will be destroyed the moment power is applied. Add a marking or a silkscreen note on the PCB to indicate 'isolated tab only' to prevent field-replace confusion.
Place the 0.33 µF input capacitor and 0.1 µF output capacitor within 5-10 mm of the IC pins using short, wide traces to suppress oscillation. Use a low-ESR ceramic or tantalum output cap; aluminum electrolytics with high ESR can trigger instability. If the upstream rectifier-capacitor filter is more than 50 mm from the regulator input, add a 10 µF bulk electrolytic at the regulator input to prevent input-voltage collapse during load transients. Keep the regulator away from switching-converter magnetics to minimize coupled noise on the analog negative rail.
Because this is a through-hole device, plan the heatsink footprint to clear adjacent tall components and to allow air-flow across the regulator tab. For multi-rail supplies using both an NJM7915FA and an NJM7815FA, mount them on the same heatsink extrusion but with their tabs on opposite sides if the FA-style isolation is used; otherwise use separate isolated heatsinks for the negative rail to avoid COMMON-to-tab short paths. Provide a small drain hole or vent at the top of tall enclosures to allow convective cooling of the heatsink.
Compliance Information
RoHS/lead-free status per Nisshinbo Micro Devices distributor listing (DigiKey). AEC-Q100 not qualified - this is a commercial-grade part. For automotive applications use automotive-qualified negative LDO variants from TI/onsemi if available.
