ESP32-WROOM-32E-H4 - WiFi BT4.2 Module 4MB | Espressif
MPN: ESP32-WROOM-32E-H4 β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.21 | $3.21 |
| 10 | $2.95 | $29.50 |
| 100 | $2.68 | $268.00 |
| 500 | $2.45 | $1,225.00 |
| 1,000 | $2.28 | $2,280.00 |
ESP32-WROOM-32E-H4 Overview
A WiFi module is a self-contained embedded system that integrates a microcontroller, radio transceiver, antenna, flash memory, and power management into a single surface-mount unit, eliminating the RF design effort of discrete solutions. Within the wireless connectivity hierarchy, the ESP32-WROOM-32E-H4 sits at the system-in-package (SiP) module level: SoC (ESP32-D0WD-V3) -> module (WROOM-32E family) -> IoT device. Modules are pre-certified for radio regulatory domains, shortening time to certification for end products.
Key features include dual-core 32-bit LX6 CPUs clocked up to 240 MHz, 520 KB on-chip SRAM, 802.11 b/g/n WiFi with up to 150 Mbps PHY rate and -98 dBm receive sensitivity, Bluetooth v4.2 BR/EDR and BLE, and 26 GPIOs with UART, SPI, I2C, SDIO, I2S, PWM, and 12-bit ADC peripherals. The -H4 suffix denotes 4 MB SPI flash; supply range is 3.0 V to 3.6 V with typical TX current around 112 mA and peak around 239 mA at 20 dBm output.
The ESP32-D0WD-V3 silicon (ECO V3) incorporates the bug fixes and cleaner WiFi RF spectrum of the revised ESP32 revision, improving coexistence and reliability compared with original ESP32-WROOM-32 modules. The onboard PCB antenna is tuned for 2.4 GHz to 2.5 GHz operation, and the metal shield plus castellated edge pads simplify reflow assembly onto standard PCB footprints.
Typical applications include smart-home devices and sensors, industrial automation and control nodes, and battery-powered IoT endpoints where integrated dual-protocol wireless reduces BOM cost and development risk.
A key design consideration: the module is 3.3 V only - do not feed 5 V logic into GPIOs without level shifting, and keep copper keep-out clearance under and around the PCB antenna per Espressif hardware design guidelines.
This page adds value beyond the datasheet by synthesizing distributor pricing tiers, drop-in same-footprint alternatives across flash densities, and practical engineering design notes in one place.
Drop-in alternatives for ESP32-WROOM-32E-H4 β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with ESP32-WROOM-32E-H4 (same form factor and footprint) β differing in Antenna, Bluetooth, CPU, Core SoC, Flash Memory.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
ESP32-WROOM-32E-N4
β Drop-Inπ Reference alternative (not in catalog)
ESP32-WROOM-32E-N8
β Drop-Inβ In Stock
$3.22 / Unit
View Datasheet βESP32-WROOM-32E-N16
β Drop-Inπ Reference alternative (not in catalog)
ESP32-WROOM-32D
β Drop-Inπ Reference alternative (not in catalog)
ESP32-WROOM-32
β Drop-Inπ Reference alternative (not in catalog)
ESP32-WROOM-32E-H4 Specifications (manufacturer-published)
| Core SoC | ESP32-D0WD-V3 (ECO V3) |
| CPU | Xtensa dual-core 32-bit LX6, up to 240 MHz |
| SRAM | 520 KB on-chip |
| Flash Memory | 4 MB SPI flash |
| WiFi Standard | 802.11 b/g/n, 2.4 GHz to 2.5 GHz |
| Bluetooth | v4.2 BR/EDR + BLE, Class 1/2/3 |
| Receive Sensitivity | -98 dBm |
| Max TX Power | 20 dBm |
| Supply Voltage | 3.0 V to 3.6 V |
| Typical TX Current | 112 mA |
| Peak Current | 239 mA |
| GPIO Count | 26 |
| Interfaces | UART, SDIO, SPI, I2C, I2S, GPIO |
| Antenna | Onboard PCB trace antenna |
| Operating Temperature | -40C to +105C |
| Package Dimensions | 25.5 x 18 mm SMD module |
| Mounting Type | Surface Mount (castellated pads) |
| RoHS Status | Compliant |
ESP32-WROOM-32E-H4 Pin Configuration
| Pin 1 | GND β Ground |
| Pin 2 | 3V3 β Power supply, 3.0 V to 3.6 V |
| Pin 3 | EN β Chip enable, active high (with pull-up) |
| Pin 4 | SENSOR_VP (GPIO36) β ADC1 CH0 / sensor VP input |
| Pin 5 | SENSOR_VN (GPIO39) β ADC1 CH3 / sensor VN input |
| Pin 6 | IO34 β GPIO34, input only, ADC1 CH6 |
| Pin 7 | IO35 β GPIO35, input only, ADC1 CH7 |
| Pin 8 | IO32 β GPIO32, ADC1 CH4, XTAL_32K_P option |
| Pin 9 | IO33 β GPIO33, ADC1 CH5, XTAL_32K_N option |
| Pin 10 | IO25 β GPIO25, ADC2 CH8, DAC1 output |
| Pin 11 | IO26 β GPIO26, ADC2 CH9, DAC2 output |
| Pin 12 | IO27 β GPIO27, ADC2 CH7, touch sensor |
| Pin 13 | IO14 β GPIO14, ADC2 CH6, touch sensor, HS2_CLK |
| Pin 14 | IO12 β GPIO12, ADC2 CH5, strapping pin (MTDI) - keep low at boot |
| Pin 15 | GND β Ground |
| Pin 16 | IO13 β GPIO13, ADC2 CH4, touch sensor |
| Pin 17 | SD2 (IO9) β SDIO data 2 / GPIO9, connected to flash - reserved |
| Pin 18 | SD3 (IO10) β SDIO data 3 / GPIO10, connected to flash - reserved |
| Pin 19 | CMD (IO11) β SDIO command / GPIO11, connected to flash - reserved |
| Pin 20 | CLK (IO6) β SDIO clock / GPIO6, connected to flash - reserved |
| Pin 21 | SD0 (IO7) β SDIO data 0 / GPIO7, connected to flash - reserved |
| Pin 22 | SD1 (IO8) β SDIO data 1 / GPIO8, connected to flash - reserved |
| Pin 23 | IO15 β GPIO15, ADC2 CH3, strapping pin (MTDO) - controls debug log at boot |
| Pin 24 | IO2 β GPIO2, ADC2 CH2, strapping pin - must be low or floating for download mode |
| Pin 25 | IO0 β GPIO0, ADC2 CH1, strapping pin - low at reset enters download mode |
| Pin 26 | IO4 β GPIO4, ADC2 CH0, touch sensor |
| Pin 27 | IO16 β GPIO16, available GPIO (not connected to PSRAM on this module) |
| Pin 28 | IO17 β GPIO17, available GPIO |
| Pin 29 | IO5 β GPIO5, strapping pin (timing of SDIO slave), VSPI CS0 |
| Pin 30 | IO18 β GPIO18, VSPI CLK |
| Pin 31 | IO19 β GPIO19, VSPI MISO / U0CTS |
| Pin 32 | NC β Not connected (per datasheet) |
| Pin 33 | IO21 β GPIO21, I2C SDA default |
| Pin 34 | RXD0 (IO3) β UART0 receive / GPIO3 |
| Pin 35 | TXD0 (IO1) β UART0 transmit / GPIO1 |
| Pin 36 | IO22 β GPIO22, I2C SCL default / U0RTS |
| Pin 37 | IO23 β GPIO23, VSPI MOSI |
| Pin 38 | GND β Ground |
Power & Thermal Characteristics
| Power Input | 3.0 V to 3.6 V |
| Operating Temperature | -40C to +105C |
Power input and thermal parameters for ESP32-WROOM-32E-H4 as published by the manufacturer.
Typical Applications
ESP32-WROOM-32E-H4 is suitable for 6 applications: Smart Home Devices and Sensors, Industrial Automation and Control Nodes, Battery-Powered IoT Endpoints, Wireless Audio and Bluetooth Classic Accessories, Gateways and Bridges (BLE to WiFi), Prototyping, Education, and Maker Products.
Smart Home Devices and Sensors
The ESP32-WROOM-32E-H4 fits smart-home products such as wall switches, plugs, sensor hubs, and door controllers because it combines 802.11 b/g/n WiFi with Bluetooth 4.2 BLE in a single pre-certified module, removing the cost of a separate BLE chip for provisioning. The -98 dBm receive sensitivity maintains robust links at the edge of a home network, while the dual-core 240 MHz LX6 handles TLS encryption and application logic concurrently without an external MCU. In a typical node the module runs ESP-IDF or Arduino firmware, connects to the home router via WiFi, and uses BLE for first-time commissioning from a phone. Its 3.0 V to 3.6 V rail integrates directly with a 3.3 V LDO supply, and the 25.5 x 18 mm castellated package reflows onto standard two-layer PCBs.
Recommended
Industrial Automation and Control Nodes
The ESP32-WROOM-32E-H4 suits industrial monitoring and light-control nodes because it is rated -40C to +105C, exceeding the 85C limit of most consumer WiFi modules, and exposes UART, SPI, I2C, SDIO, and PWM interfaces for PLC-adjacent I/O. The dual-core architecture lets one core run the WiFi/BLE stack while the other handles deterministic control loops or Modbus parsing over UART, and the 26 GPIOs with 12-bit ADC support analog sensor acquisition. The metal shield provides EMI containment near drives and contactors, and the 20 dBm max TX power sustains links across a factory floor. Design the 3.3 V supply for 239 mA peak with adequate decoupling, and observe the PCB antenna keep-out specified in the Espressif hardware design guidelines to preserve RF performance inside metal-dense enclosures.
Recommended
Battery-Powered IoT Endpoints
For battery-powered IoT endpoints such as asset trackers, environmental loggers, and portable meters, the ESP32-WROOM-32E-H4 offers deep-sleep operation on the ESP32-D0WD-V3 with wake-on-timer or GPIO, allowing devices to sleep in the microamp range between periodic WiFi transmissions. The 3.0 V to 3.6 V supply range matches a single lithium cell through an LDO or runs directly from a regulated pack. Typical duty-cycled designs wake, sample a sensor over I2C, transmit a JSON payload over WiFi or BLE in tens of milliseconds at roughly 112 mA, then return to deep sleep, yielding months of runtime on 2x AA cells depending on reporting interval. The -98 dBm sensitivity reduces transmit retries at weak signal locations, which directly lowers average battery drain.
Recommended
Wireless Audio and Bluetooth Classic Accessories
The ESP32-WROOM-32E-H4 is one of the few low-cost modules with Bluetooth Classic BR/EDR, making it appropriate for A2DP audio receivers, Bluetooth-bridged speakers, and legacy BT peripheral links that BLE-only chips cannot serve. The dual-core LX6 runs the BT stack and I2S audio output concurrently, streaming to an external I2S DAC over the module's I2S pins, while WiFi remains available for networked audio modes. Espressif's ESP-IDF provides maintained A2DP sink/source examples, and community projects such as ESP32-A2DP target this exact silicon (ECO V3 recommended for stable RF). The 239 mA peak current requires a supply designed for simultaneous WiFi TX and audio processing, and the onboard PCB antenna keeps the BOM free of external antenna parts.
Recommended
Gateways and Bridges (BLE to WiFi)
As a BLE-to-WiFi gateway, the ESP32-WROOM-32E-H4 aggregates data from BLE sensor meshes and forwards it to cloud MQTT endpoints, exploiting its simultaneous Bluetooth and WiFi operation confirmed in Espressif documentation. The dual-core split is ideal here: one core services BLE connections from nodes such as thermometers or beacons while the other maintains the TLS-secured WiFi uplink, with 520 KB SRAM and 4 MB flash supporting buffering and OTA updates. The 802.11 b/g/n stack handles standard 2.4 GHz infrastructure networks at up to 150 Mbps PHY rate. Placement matters for RF: keep the PCB antenna edge overhanging the enclosure or adjacent to a plastic window, and respect the datasheet keep-out so both radios achieve specified range in dense deployments.
Recommended
Prototyping, Education, and Maker Products
The ESP32-WROOM-32E-H4 is the module of choice for prototyping boards and small-run maker products because it is supported by Arduino, ESP-IDF, MicroPython, and PlatformIO, with the largest community knowledge base of any ESP32 module. Its castellated pads allow hand soldering or castellation-edge mounting on simple carrier PCBs, and the ECO V3 silicon avoids early-revision WiFi and boot bugs documented in older WROOM-32 designs. Development boards built on the 32E, including updated 30/38-pin DevKit clones, use exactly this module, so firmware developed on a devkit transfers to a production board with the same module unchanged. At roughly $3.21 per unit, it is also economical for classroom kits and hackathon hardware at volume.
Recommended
Recommended Products Summary
Engineering reference data for ESP32-WROOM-32E-H4 β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ESP32-WROOM-32E-N4 | ESP32-WROOM-32E-N8 | ESP32-WROOM-32E-N16 | ESP32-WROOM-32D | ESP32-WROOM-32 |
|---|---|---|---|---|---|---|
| Package | 25.5 x 18 mm SMD castellated module, PCB antenna | 25.5 x 18 mm - same | 25.5 x 18 mm - same | 25.5 x 18 mm - same | 25.5 x 18 mm - same | 25.5 x 18 mm - same |
| Brand | Espressif Systems | Espressif Systems | Espressif Systems | Espressif Systems | Espressif Systems | Espressif Systems |
| SoC / Silicon Revision | ESP32-D0WD-V3 (ECO V3) | ESP32-D0WD-V3 (ECO V3) | ESP32-D0WD-V3 (ECO V3) | ESP32-D0WD-V3 (ECO V3) | ESP32-D0WD (earlier revision) | ESP32-D0WDQ6 (original revision) |
| Flash Memory | 4 MB SPI | 4 MB SPI | 8 MB SPI | 16 MB SPI | 4 MB SPI | 4 MB SPI |
| WiFi / Bluetooth | 802.11 b/g/n + BT 4.2 BR/EDR/BLE | 802.11 b/g/n + BT 4.2 BR/EDR/BLE | 802.11 b/g/n + BT 4.2 BR/EDR/BLE | 802.11 b/g/n + BT 4.2 BR/EDR/BLE | 802.11 b/g/n + BT 4.2 BR/EDR/BLE | 802.11 b/g/n + BT 4.2 BR/EDR/BLE |
| Receive Sensitivity / TX Power | -98 dBm / 20 dBm | -98 dBm / 20 dBm | -98 dBm / 20 dBm | -98 dBm / 20 dBm | -98 dBm / 20 dBm | -98 dBm / 20 dBm |
| Operating Temperature | -40C to +105C | -40C to +105C | -40C to +105C | -40C to +105C | -40C to +85C | -40C to +85C |
| Silicon Bug Fixes / RF Quality | ECO V3 - fixed errata, cleaner WiFi spectrum | ECO V3 - same | ECO V3 - same | ECO V3 - same | Earlier revision - fewer fixes | Original revision - known errata |
Key Differentiators
- 105C industrial temperature rating (vs ESP32-WROOM-32D)
- ECO V3 silicon with cleaner WiFi RF spectrum (vs ESP32-WROOM-32)
- Flash scalability on an identical footprint (vs ESP32-WROOM-32E-N8)
Design Notes
Design the 3.3 V rail for at least 500 mA with 239 mA peak WiFi TX current in mind. Place a 10 uF bulk ceramic capacitor and a 100 nF decoupling capacitor within 2 mm of the 3V3 pin (pin 2). Inrush during WiFi TX bursts causes brown-out resets if the supply impedance is too high - this is the single most common ESP32 field failure. If using an LDO, choose one rated 500 mA+ with good transient response (e.g., a low-dropout regulator sized for 3.6 V max input from a 5 V rail). Estimated: at 3.3 V and 239 mA peak, module power is approximately 0.79 W during TX bursts only.
Keep the module edge with the PCB antenna (short edge opposite the castellated pads area indicated by the antenna keep-out in the Espressif hardware design guidelines) free of copper on ALL layers, including ground planes. Place the antenna section overhanging the board edge or over a plastic enclosure window. Do not route traces, bury vias, or place batteries/metal under the antenna region. Follow the Espressif 'ESP32 Hardware Design Guidelines' keep-out dimensions exactly - violating the keep-out can cost 10-20 dB of radiated performance.
Respect the strapping pins at reset: GPIO0 (pin 25) low enters the serial download mode; GPIO12 (pin 14) must be low at boot or the flash voltage is misconfigured and boot fails; GPIO2 (pin 24) must be low or floating for download mode; GPIO15 (pin 23) silences boot log when low. Never attach push-pull peripherals to GPIO12. Also note pins 17-22 (SD2/SD3/CMD/CLK/SD0/SD1) are wired to the internal SPI flash and must not be used as GPIO. The NC pin 32 must remain unconnected.
Pull EN (pin 3) high with a 10 kR resistor and add a 1 uF capacitor to EN to GND for a controlled power-on reset; add a reset button pulling EN low. For flashing, expose GPIO0 with a jumper to GND and break out UART0 TX/RX (pins 35/34) on a header. Enable the module's internal circuitry by not loading the flash-reserved pins. These provisions match the reference schematic in the ESP32-WROOM-32E datasheet typical application circuit.
Compliance Information
RoHS compliance per LCSC and JLCPCB listings (C3013935). Module carries regional radio certifications via Espressif; confirm target-market certs on the Espressif product page. No AEC-Q100 claim for this commercial module.
