English
Three voltage variants — 3V (1.5–4.5V), 5V (3–7V), and 12V (8–16V) — sharing the same resonant frequency specification of 2700 ± 300 Hz
Integrated oscillator circuit — DC application generates fixed-tone output without external PWM or signal conditioning
≥85 dB sound pressure at 10 cm — specified minimum across all three variants at respective rated voltages
0.71 g lightweight body (per specification)
Black PBT housing; operating temperature -20 °C to +70 °C, storage temperature -30 °C to +80 °C
4.2 mm height profile (per specification)
| Parameter | HNT-9042-03 | HNT-9042-05 | HNT-9042-12 |
| Rated Voltage | 3 V DC | 5 V DC | 12 V DC |
| Operating Voltage | 1.5 – 4.5 V DC | 3 – 7 V DC | 8 – 16 V DC |
| Sound Output at 10 cm | ≥ 85 dB | ≥ 85 dB | ≥ 85 dB |
| Operating Current | ≤ 30 mA | ≤ 30 mA | ≤ 30 mA |
| Resonant Frequency | 2700 ± 300 Hz | 2700 ± 300 Hz | 2700 ± 300 Hz |
| Operating Temperature | -20 °C ~ +70 °C | -20 °C ~ +70 °C | -20 °C ~ +70 °C |
| Storage Temperature | -30 °C ~ +80 °C | -30 °C ~ +80 °C | -30 °C ~ +80 °C |
| Dimensions (Dia × H) | 9.0 × 4.2 mm | 9.0 × 4.2 mm | 9.0 × 4.2 mm |
| Weight | 0.71 g | 0.71 g | 0.71 g |
| Housing Material | Black PBT | Black PBT | Black PBT |
Compact 9.0 × 4.2 mm footprint — specified dimensions for through-hole mounting
Integrated oscillator eliminates external drive — DC voltage application generates fixed 2700 ± 300 Hz tone without external PWM or signal generator
Three voltage tiers — 3V, 5V, and 12V variants enable selection based on available system voltage rail
0.71 g weight — per specification
Polarized through-hole mounting — pin polarity marking indicates correct orientation
Black PBT housing for industrial assembly — compatible with wave soldering at 255 ± 15 °C and manual soldering at 360 ± 10 °C per specification
≤ 30 mA current draw at rated voltage — specified maximum operating current
| Parameter | Value | Test Conditions |
| Product Type | Electromagnetic Through-Hole Active Buzzer | — |
| Rated Voltage | 3 V DC | Nominal operating point |
| Operating Voltage | 1.5 – 4.5 V DC | Continuous range |
| Sound Output at 10 cm | ≥ 85 dB | At 3V, free field |
| Operating Current | ≤ 30 mA | At 3V |
| Resonant Frequency | 2700 ± 300 Hz | At rated voltage |
| Operating Temperature | -20 °C ~ +70 °C | Continuous |
| Storage Temperature | -30 °C ~ +80 °C | Non-operating |
| Dimensions (Dia × H) | 9.0 × 4.2 mm | Body excluding pins |
| Weight | 0.71 g | Typical |
| Housing Material | Black PBT | — |
| Soldering (Reflow) | 245 ± 15 °C, 3 s | 180 °C preheat 40–70 s; max 3 passes |
| Soldering (Wave) ★ | 255 ± 15 °C, 4–6 s | 2–3 passes recommended |
| Soldering (Manual) ★ | 360 ± 10 °C, 2–5 s | 2–3 passes recommended |
| Parameter | Value | Test Conditions |
| Product Type | Electromagnetic Through-Hole Active Buzzer | — |
| Rated Voltage | 5 V DC | Nominal operating point |
| Operating Voltage | 3 – 7 V DC | Continuous range |
| Sound Output at 10 cm | ≥ 85 dB | At 5V, free field |
| Operating Current | ≤ 30 mA | At 5V |
| Resonant Frequency | 2700 ± 300 Hz | At rated voltage |
| Operating Temperature | -20 °C ~ +70 °C | Continuous |
| Storage Temperature | -30 °C ~ +80 °C | Non-operating |
| Dimensions (Dia × H) | 9.0 × 4.2 mm | Body excluding pins |
| Weight | 0.71 g | Typical |
| Housing Material | Black PBT | — |
| Soldering (Reflow) | 245 ± 15 °C, 3 s | 180 °C preheat 40–70 s; max 3 passes |
| Soldering (Wave) ★ | 255 ± 15 °C, 4–6 s | 2–3 passes recommended |
| Soldering (Manual) ★ | 360 ± 10 °C, 2–5 s | 2–3 passes recommended |
| Parameter | Value | Test Conditions |
| Product Type | Electromagnetic Through-Hole Active Buzzer | — |
| Rated Voltage | 12 V DC | Nominal operating point |
| Operating Voltage | 8 – 16 V DC | Continuous range |
| Sound Output at 10 cm | ≥ 85 dB | At 12V, free field |
| Operating Current | ≤ 30 mA | At 12V |
| Resonant Frequency | 2700 ± 300 Hz | At rated voltage |
| Operating Temperature | -20 °C ~ +70 °C | Continuous |
| Storage Temperature | -30 °C ~ +80 °C | Non-operating |
| Dimensions (Dia × H) | 9.0 × 4.2 mm | Body excluding pins |
| Weight | 0.71 g | Typical |
| Housing Material | Black PBT | — |
| Soldering (Reflow) | 245 ± 15 °C, 3 s | 180 °C preheat 40–70 s; max 3 passes |
| Soldering (Wave) ★ | 255 ± 15 °C, 4–6 s | 2–3 passes recommended |
| Soldering (Manual) ★ | 360 ± 10 °C, 2–5 s | 2–3 passes recommended |
Note: The following data is extracted from the test reports attached to the MEIDI product specifications. These values illustrate typical distribution from sampled production batches and are not guaranteed specifications.
| Variant | SPL Range (dB) | Current Range (mA) | Frequency Range (Hz) | Dia (mm) | H (mm) |
| HNT-9042-03 | 86.5 – 89.5 | 22.8 – 26.5 | 2690 – 2730 | 9.07 – 9.15 | 4.20 – 4.22 |
| HNT-9042-05 | 86.5 – 89.5 | 24.5 – 26.1 | 2677 – 2723 | 9.0 – 9.1 | 4.20 – 4.22 |
| HNT-9042-12 | 87.3 – 89.9 | 24.9 – 26.5 | 2677 – 2723 | 9.11 – 9.12 | 4.25 – 4.21* |
Note: HNT-9042-12 sample data line 2 shows H dimension 42.1 mm, which is a typographical error in the original test report; the specified dimension is 4.2 ± 0.2 mm.
Guaranteed specifications are listed in the Technical Specifications tables above. Contact MEIDI for actual batch test data.
Handheld test and measurement instruments — audible completion and threshold alerts in multimeters, oscilloscopes, and field calibrators
Portable medical devices — battery-operated glucose monitors, pulse oximeters, and nebulizers requiring low-profile acoustic alerts
Consumer electronics and small appliances — microwave timers, coffee maker completion chimes, and air purifier filter replacement alerts
Battery-backed security sensors — door/window contact sensors, motion detectors, and smoke alarm test signals
Telecommunications equipment — rack-mounted UPS fault alerts, network switch status tones, and PBX system audible feedback
Educational and hobby electronics — Arduino and Raspberry Pi project audio feedback
| Design Consideration | HNT-9042 Series Feature |
| Compact footprint | 9.0 × 4.2 mm specified dimensions |
| Multiple system voltages | Three variants (3V/5V/12V) share the same resonant frequency specification of 2700 ± 300 Hz |
| Simplified drive circuitry | Integrated oscillator eliminates external PWM generator or microcontroller timer |
| Through-hole mounting | Lead-through PCB mounting provides mechanical retention |
| Mixed-technology assembly | PBT housing compatible with wave soldering and manual rework per specification |
Request a sample to evaluate sound pressure, current consumption, and height clearance in your target enclosure.
The MEIDI 9042 Electromagnetic Active Buzzer specifications define the following reliability tests:
High-temperature storage — 48 hours at +80 ± 2 °C, restore at room temperature for 2 hours before testing
Low-temperature storage — 48 hours at -30 ± 2 °C, restore at room temperature for 2 hours before testing
Temperature cycling — 5 cycles: -30 °C exposure 30 min, +80 °C exposure 30 min; restore at room temperature for 2 hours before testing
Drop test — horizontal position, free fall from 75 cm to 10 mm hardwood board, 3 drops; check appearance and measure electrical performance
Vibration test — 10–55 Hz, 1.0 mm amplitude, XYZ axes, 0.5 hours total; sweep time from 10 to 55 Hz and back under single amplitude of 1.0 mm is 1 minute
Humidity test — 48 hours at 50 ± 5 °C / 90–95% RH, restore at room temperature for 2 hours before testing
Solder heat resistance — immerse leads in molten solder at 250 ± 5 °C for 10 ± 0.5 seconds, body 2.0 mm from solder
Note: All test conditions are as specified in the MEIDI HNT-9042 Series product specification dated 2023-11-07. Contact MEIDI for production test protocol details and actual batch test data.
1. How do I select between the HNT-9042-03, HNT-9042-05, and HNT-9042-12?
Selection depends on your available DC supply voltage. The HNT-9042-03 (1.5–4.5V) is suited for 3.3V logic systems and low-voltage microcontroller projects. The HNT-9042-05 (3–7V) matches 5V industrial logic and standard appliance control voltages. The HNT-9042-12 (8–16V) is designed for 12V industrial control buses and security system power supplies. All three variants share the same resonant frequency specification of 2700 ± 300 Hz and the same minimum sound pressure specification.
2. Can I use the HNT-9042-03 with a 3.3V microcontroller GPIO pin?
The HNT-9042-03 operating voltage range is 1.5–4.5V DC, which includes 3.3V. However, the ≤30 mA operating current at 3V must be verified against the microcontroller pin current sourcing capability. Verify that the driving source can provide ≤30 mA at the operating voltage. Contact MEIDI for drive circuit recommendations if needed.
3. What is the minimum enclosure height above the HNT-9042 sound hole?
Ensure adequate clearance above the sound hole to avoid sound pressure degradation. Refer to the precautions in the MEIDI product specification.
4. Is the HNT-9042 Series suitable for continuous operation?
The operating temperature range is -20 °C to +70 °C per specification. For continuous operation inquiries, contact MEIDI.
5. Can the HNT-9042 Series replace a passive buzzer in an existing design?
The HNT-9042 is an active buzzer with integrated oscillator, while passive buzzers require an external AC drive signal. Replacing a passive buzzer with an HNT-9042 active buzzer requires circuit modification: remove the external drive circuit and connect the HNT-9042 directly to the appropriate DC voltage rail. The through-hole pin configuration may differ from the passive buzzer footprint; verify pin diameter, pitch, and polarity against the original PCB layout. Contact MEIDI for replacement feasibility assessment.
1.Do not apply voltage beyond the specified operating voltage range.
2.This product is of open design and does not meet waterproof or glue-leakage requirements.
3.Prolonged use in an environment with corrosive gas may corrode the buzzer components and prevent proper operation.
4.The sound pressure performance of the buzzer will change with the applied voltage or current; ensure the operating voltage or current meets the specification requirements.
5.Avoid placing a baffle in front of the sound hole or covering it, as this may lead to unstable operation.
6.The buzzer should be stored in proper packaging to avoid moisture, rust, and oxidation of the pin terminals.
For cross-reference verification against legacy through-hole buzzers, series datasheets, sample evaluation of voltage variants, or custom lead configurations, contact MEIDI Applications Engineering.
Address
No.6, Wenlin Road, Chenbao Town, Xinghua City, Jiangsu Province, China
Tel
