Can the 1N4001G be used in 120 V mains rectification?

No. The 1N4001G is rated for only 50 V reverse voltage. For 120 V mains, use at least 1N4004G (400 V) or 1N4007G (1000 V) to handle peak voltages safely.

What is the maximum continuous current for the 1N4001G?

The 1N4001G is rated for 1 A average forward current. For reliable operation, keep continuous current below this limit and consider thermal design at full load.

Is the 1N4001G RoHS compliant?

Yes, the “G” suffix typically indicates a lead-free, RoHS-compliant version. Good-Ark Electronics’ 1N4001G follows this convention and is suitable for modern environmentally compliant designs.

Can I replace a 1N4007G with a 1N4001G?

Only if the circuit’s peak reverse voltage is below 50 V. Otherwise, replacing a higher-voltage diode with the 1N4001G can cause failure under normal operation.

What package does the 1N4001G use?

The 1N4001G uses a DO-41 (DO-204AL) axial through-hole package, with a polarity band marking the cathode terminal.

What is the difference between the 1N4001G and the 1N4001G-T?

They are electrically identical. The “-T” suffix on the Diodes Incorporated part number indicates tape-and-reel packaging for automated assembly; the die, 50 V / 1 A ratings, and DO-41 package are the same.

What is the difference between the 1N4001G and the 1N4007G?

Both are 1 A rectifiers in the same DO-41 package with similar forward voltage. The only meaningful difference is reverse voltage: 50 V for the 1N4001G versus 1000 V for the 1N4007G. A 1N4007G can replace a 1N4001G with extra margin, but the 1N4001G must never be used where more than 50 V blocking is required.

What Is the 1N4001G Rectifier Diode and What Are Its Key Specs?

Quick answer: The 1N4001G is a 1 A, 50 V glass-passivated rectifier diode in a DO-41 axial package. Use it for low-voltage AC-to-DC conversion, small battery chargers, and reverse-polarity protection in 50/60 Hz circuits. It is not designed for 120 V mains or high-frequency switching.

(Last modified date: August 31, 2026)

The 1N4001G is a 1 A, 50 V general-purpose silicon rectifier diode in a DO-41 axial package. It features low forward voltage, low leakage, and a glass-passivated junction, making it ideal for small battery chargers, power supplies, and low-power AC/DC conversion.

Key Takeaways

The 1N4001G is a 50 V, 1 A general-purpose rectifier, the entry point of the 1N400x family for low-voltage DC supplies.
Confirm reverse voltage headroom, surge rating, and thermal derating against the application; see general-purpose rectifier selection.
For higher voltage rails, move up the family: 1N4002G and 1N4004G.
The 1N4001G covers 50 V, 1 A rectification in the classic DO-41 package.

What exactly is the 1N4001G diode?

The 1N4001G is a 1 A average forward current, 50 V peak repetitive reverse voltage silicon rectifier diode in a DO-41 axial package. It is designed for general-purpose rectification in low-power AC/DC circuits such as small battery chargers and DC power supplies.

The 1N4001G belongs to the standard 1N400xG family (1N4001G–1N4007G). Note that the meaning of the “G” suffix depends on the manufacturer: it indicates a glass-passivated junction in parts from onsemi and Good-Ark, while Diodes Incorporated uses it for a lead-free, RoHS-compliant version. Always confirm the suffix convention on the specific datasheet; the electrical performance is identical.

Manufactured by several vendors, including Good-Ark Electronics, it uses a diffused junction with glass passivation for stable high-temperature operation and low leakage current. Its simple two-terminal, axial design makes it easy to insert in PCBs or through-hole assemblies, while the polarity band clearly marks the cathode. The device is widely used wherever reliable, low-cost rectification is needed in consumer electronics, industrial control, and power conversion applications.

Which electrical parameters define the 1N4001G performance?

Key parameters: 50 V repetitive peak reverse voltage (VRRM), 1 A average forward current (IF(AV)), 30 A peak surge current (IFSM), 1.1 V max forward drop (VF at 1 A), and 5 µA max reverse leakage at 50 V. The 1N4001G’s electrical performance is defined by a set of standard rectifier specifications, all listed in the Good-Ark 1N4001G–1N4007G datasheet:

Parameter	Symbol	Value (1N4001G)	Unit
Repetitive peak reverse voltage	VRRM	50	V
RMS reverse voltage	VRMS	35	V
DC blocking voltage	VDC	50	V
Average forward current	IF(AV)	1	A
Peak surge current (8.3 ms)	IFSM	30	A
Forward voltage drop	VF	1.1 (at 1 A)	V
Reverse leakage current	IR	5 (at 50 V, 25 °C)	µA
Junction capacitance	CJ	~15 (4 V, 1 MHz)	pF
Reverse recovery time	trr	~1	µs

These values make the 1N4001G well-suited for mains-derived low-voltage DC supplies, battery chargers, and signal-level rectification where fast switching is not critical. Compared with higher-voltage members of the 1N400xG series, the 1N4001G is optimized for low-voltage, high-reliability applications. Good-Ark Electronics emphasizes low leakage and low forward drop in its 1N4001G product line, helping reduce power loss and improve efficiency in compact power supplies.

How does the 1N4001G differ from other 1N400xG diodes?

The 1N4001G is the 50 V version of the 1N400xG series; other members range from 100 V to 1000 V. All share 1 A current, similar forward drop, and DO-41 package, differing mainly in VRRM.

Within the 1N400xG family, the only significant difference between devices is their maximum repetitive peak reverse voltage (VRRM). The 1N4001G is rated for 50 V, while:

1N4002G: 100 V
1N4003G: 200 V
1N4004G: 400 V
1N4005G: 600 V
1N4006G: 800 V
1N4007G: 1000 V

All variants maintain 1 A average forward current, ~1.1 V forward drop at 1 A, and the same DO-41 axial package. This means that for low-voltage supplies (e.g., 12 V or 24 V DC outputs from a 24–30 V RMS transformer), the 1N4001G is often sufficient and slightly more cost-effective. For mains-derived supplies where peak reverse voltages can exceed 300–400 V, designers typically choose 1N4004G or 1N4007G for safety margin.

Choosing the 1N4001G instead of a higher-voltage variant should be based on actual peak reverse voltage in the circuit, not habit. In many modern low-voltage SMPS and battery charger designs, the 1N4001G is the optimal choice when voltage stress is low.

1N4001G equivalents and cross-references

If you need to source or substitute a 1N4001G, the following are the most common cross-reference paths:

Direct equivalents: any 1N4001 or 1N4001G from onsemi, Diodes Incorporated, Vishay, Taiwan Semiconductor, Rectron, or Good-Ark is electrically equivalent in the DO-41 package. Check the datasheet for VRRM, IF, IFSM, and package before substituting.
Tape-and-reel variants: the 1N4001G-T part number (Diodes Incorporated) uses the same die and package but is supplied in tape-and-reel form for automated assembly. It is electrically identical.
Higher-voltage drop-ins: 1N4002G through 1N4007G fit the same footprint and current rating, adding reverse-voltage margin. Many teams standardize on the 1N4007G to simplify inventory across designs.
Safety rule: never replace a higher-voltage diode with the 1N4001G unless the circuit’s peak reverse voltage stays below 50 V with margin. The reverse substitution (1N4001G in a low-voltage slot) is safe.

How to test a 1N4001G and spot common failure signs?

A multimeter in diode-test mode is all you need to check a 1N4001G in seconds. Testing the part before assembly, or when a board fails, distinguishes a bad diode from a problem elsewhere in the circuit.

Set the multimeter to diode-test mode.
Identify the anode and cathode; the cathode is marked by the band on the DO-41 body.
Forward test: place the red probe on the anode and the black probe on the cathode. A healthy silicon diode reads roughly 0.5–0.7 V (some meters show up to ~1.1 V at higher current).
Reverse test: swap the probes. A healthy diode reads OL (open / over-range) in the reverse direction.
Repeat both tests once to confirm consistent readings.

Common failure signs:

Reads near 0 V in both directions: the diode is shorted. Current bypasses the junction and downstream protection is lost.
OL in both directions: the diode is open. The circuit loses its rectification or protection path entirely.
Finite reading in reverse: the diode is leaky and may pass current in the wrong direction under load, causing overheating.
Physical damage: a cracked or charred body, discolored leads, or a burnt PCB trace around the part usually indicates a surge or sustained overload.

Test the diode out of circuit when possible; in-circuit readings can be skewed by parallel components. If the part tests healthy but the board still fails, check the soldering and the surrounding drive circuit before replacing the diode.

Simulating the 1N4001G in SPICE

The 1N4001G is a standard-recovery rectifier, which makes it a common default part in SPICE-based circuit simulation. A typical 1N4001 SPICE model uses a breakdown voltage of 50 V, a saturation current in the nanoamp range, a series resistance below 1 Ω, and a junction capacitance around 8–15 pF. Exact values vary by vendor, so use the model card published by the manufacturer rather than typing parameters by hand.

In LTspice, you can place a diode and load the vendor’s 1N4001 model, then run a bridge-rectifier test circuit to check output ripple, diode current, and power dissipation before breadboarding. Simulating the 50 V blocking limit and 30 A surge conditions also helps you confirm margin in the actual circuit without risking hardware.

Where is the 1N4001G typically used in power circuits?

Common uses: small battery chargers, low-power AC/DC converters, DC power supplies, and general rectification in consumer electronics. It handles up to 1 A and 50 V reverse, ideal for low-voltage designs.

The 1N4001G is most frequently found in:

Small battery chargers: for 6–12 V batteries, where secondary rectification or simple half-wave/full-wave rectification is needed.
Low-power DC power supplies: in transformer-based supplies with output voltages up to ~30–35 V DC, where the 50 V rating is adequate.
Signal and bias rectification: in circuits that convert small AC signals to DC for biasing or detection.
Protection and clamping: as a basic rectifying or clamping element in low-energy circuits.

Because of its 1 A current rating, it is not suitable for high-current outputs but is ideal for control circuits, small auxiliary supplies, and low-power consumer electronics. Its robust surge capability (30 A) also helps handle transient conditions during startup or line surges. Good-Ark Electronics targets applications such as SMPS power supplies, home appliances, and industrial power equipment with its 1N4001G and related rectifier products, leveraging its complete supply chain from wafer to packaging.

Why choose the 1N4001G over Schottky or fast rectifiers?

The 1N4001G offers low cost, high surge capability, and proven reliability for low-frequency rectification. Schottky/fast diodes are better for high-frequency SMPS, but 1N4001G is ideal for simple, low-cost, low-voltage designs.

Schottky and fast-recovery diodes excel in high-frequency switched-mode power supplies (SMPS) due to lower forward drop and shorter reverse recovery. However, the 1N4001G remains attractive for:

Low-frequency rectification: in transformer-based supplies at 50/60 Hz, reverse recovery time is not critical.
Cost sensitivity: the 1N4001G is extremely inexpensive and widely available.
Surge robustness: its 30 A surge rating is higher than many small Schottky devices.
Simplicity: no need for complex snubber or EMI mitigation in many low-power designs.

For circuits where efficiency is not paramount and operating frequencies are low, the 1N4001G provides a reliable, economical solution. In higher-frequency or higher-efficiency designs, designers may prefer Schottky or fast rectifiers, but for many general-purpose applications, the 1N4001G is still the default choice. Good-Ark Electronics positions its 1N4001G as a general-purpose rectifier optimized for low leakage and low forward drop, balancing performance and cost for mass-market power electronics.

Good-Ark Electronics Expert Views

“The 1N4001G represents a classic, high-reliability solution for low-voltage, low-current rectification in a wide range of consumer and industrial applications. At Good-Ark Electronics, we focus on optimizing junction passivation and forward characteristics to reduce leakage and power loss, while maintaining the robust surge capability that designers expect from the 1N400xG family. For modern low-voltage SMPS and battery charger designs, the 1N4001G often remains the most cost-effective and dependable choice when voltage stress is limited.” — Good-Ark Electronics Power Rectifier Team

How to correctly implement the 1N4001G in a circuit?

Connect the 1N4001G with the polarity band (cathode) toward the positive output in rectifier circuits. Respect 50 V reverse and 1 A continuous current limits, and ensure adequate PCB spacing and thermal path for 1 A operation.

When using the 1N4001G:

Orientation: the polarity band marks the cathode; in a standard rectifier, the cathode goes to the positive side of the load.
Voltage margin: ensure the peak reverse voltage in your circuit stays well below 50 V, ideally with 20–30% margin.
Current rating: keep continuous current below 1 A; for marginal conditions, consider parallel devices or a higher-current diode.
Thermal design: at 1 A with ~1.1 V drop, power loss is ~1.1 W. Provide reasonable PCB copper area and, if needed, airflow to avoid excessive junction temperature.
Surge protection: in mains-connected designs, add fuses or inrush limiters to protect the diode from excessive surges beyond its 30 A capability.

Proper implementation ensures long life and stable performance, especially in environments with temperature variations or frequent on/off cycling.

Conclusion

The 1N4001G is a versatile, low-cost 1 A, 50 V rectifier diode ideal for small battery chargers, low-power AC/DC converters, and general rectification tasks. Its glass-passivated junction, low forward drop, and high surge capability make it a dependable choice in many consumer and industrial power applications. It covers 50 V, 1 A rectification in the classic DO-41 package, with direct equivalents across major manufacturers and easy drop-in paths to higher-voltage family members when margin is needed.

For designers working on low-voltage power supplies, the 1N4001G often remains the most practical and economical solution when voltage stress is limited. For datasheets, cross-reference support, or sample requests, see the Good-Ark sample and quote guide.

FAQs

Can the 1N4001G be used in 120 V mains rectification? No. The 1N4001G is rated for only 50 V reverse voltage. For 120 V mains, use at least 1N4004G (400 V) or 1N4007G (1000 V) to handle peak voltages safely.
What is the maximum continuous current for the 1N4001G? The 1N4001G is rated for 1 A average forward current. For reliable operation, keep continuous current below this limit and consider thermal design at full load.
Is the 1N4001G RoHS compliant? Yes, the “G” suffix typically indicates a lead-free, RoHS-compliant version. Good-Ark Electronics’ 1N4001G follows this convention and is suitable for modern environmentally compliant designs.
Can I replace a 1N4007G with a 1N4001G? Only if the circuit’s peak reverse voltage is below 50 V. Otherwise, replacing a higher-voltage diode with the 1N4001G can cause failure under normal operation.
What package does the 1N4001G use? The 1N4001G uses a DO-41 (DO-204AL) axial through-hole package, with a polarity band marking the cathode terminal.
What is the difference between the 1N4001G and the 1N4001G-T? They are electrically identical. The “-T” suffix on the Diodes Incorporated part number indicates tape-and-reel packaging for automated assembly; the die, 50 V / 1 A ratings, and DO-41 package are the same.
What is the difference between the 1N4001G and the 1N4007G? Both are 1 A rectifiers in the same DO-41 package with similar forward voltage. The only meaningful difference is reverse voltage: 50 V for the 1N4001G versus 1000 V for the 1N4007G. A 1N4007G can replace a 1N4001G with extra margin, but the 1N4001G must never be used where more than 50 V blocking is required.