EH-MB18 Bluetooth® Technology Audio Module • Bluetooth radio - Fully embedded Bluetooth® v4.2(Smart ready) Bluetooth® v3.0 specification compliant TX power +8dbm,-90dbm RX sensitivity 128-bit encryption security Range up to 15m Internal chip antenna or U.
Bluetooth Audio Module 1. Contents 1. Description .........................................................................................................................................................4 2. Application .........................................................................................................................................................4 3. EH-MB18 Product numbering ......................................................................................................
Bluetooth Audio Module 8. Mechanical and PCB Footprint Characteristics ...................................................................................... 27 9. RF Layout Guidelines .................................................................................................................................... 28 10. Reflow Profile............................................................................................................................................... 29 11.
Bluetooth Audio Module 1. Description The EH-MB18 is an easy to use Bluetooth module, compliant with Bluetooth v4.2. The module provides complete RF platform in a small form factor. The module enables electronic devices with wireless connectivity, not requiring any RF experience or expertise for integration into the final product. The module being a certified solution optimizes the time to market of the final application.
Bluetooth Audio Module 4. Electrical Characteristic 4.1. Recommend operation conditions Operating Condition Min Typical Max Unit Operating Temperature Range -40 -- +85 °C PIO Voltage +1.7 +3.3 +3.6 V AIO Voltage +1.7 +1.8 +1.95 V LED +1.1 3.7 +3.6 V VDD Voltage +2.7 +3.3 +3.6 V VCHG(a) +4.75 +5 +5.75 V RF frequency 2400 2441 24800 MHz Table 1: Recommended Operating Conditions Note:(a) Maximum charging current 200mA 4.2.
Bluetooth Audio Module N/A Inquiry a n d page s c a n Inquiry = 1280m s interval Page = 1280m s interval W indo w = 11.25m s uA - 378 Master ACL Sniff = 500ms, 1 attempt, 0 timeout DH1 119 uA Master ACL Sniff = 1280ms, 8 attempts, 1 timeout DH1 109 uA Master SCO Sniff = 100ms, 1 attempt, PCM HV3 7.6 mA Master SCO Sniff = 100ms, 1 attempt, mono audio codec HV3 9.8 mA Master eSCO Setting S3, sniff = 100ms, PCM 2EV3 5.
Bluetooth Audio Module 100ms, PCM Slave eSCO Setting S3, sniff = 100ms, mono audio codec 2EV3 8.2 mA Slave eSCO Setting S3, sniff = 100ms, mono audio codec 3EV3 7.9 mA Table 3: Power consumptions Note : Current consumption values are taken with: ■ Firmware ID = 7919 ■ RF TX power set to 0dBm ■ No RF retransmissions in case of eSCO ■ Audio gateway transmits silence when SCO/eSCO channel is open ■ LEDs disconnected ■ AFH off 4.4. Input/output Terminal Characteristics 4.4.1.
Bluetooth Audio Module Table 4: Digital Terminal 4.4.2. USB Min VDD_USB for correct USB operation Type Max Unit 3.10 3.30 3.60 V - - Input Threshold VIL input logic level low VIH input logic level high 0.70 x VDD_US B 0.30 x VDD_US B V - - V Input Leakage Current VSS_DIG < VIN < VDD_USB(a) -1 1 5 µA CI input capacitance 2.5 - 10 pF 0.2 V Output Voltage Levels to Correctly Terminated USB Cable VOL output logic level low 0 - VOH output logic level high 2.
Bluetooth Audio Module 2 (20kHz max) A-Weighted THD+N < 0.1% 1.6Vpk-pk input SNR fin = 1kHz B/W = 20Hz→Fsample/ 2 (20kHz max) 1.6Vpk-pk input THD+N Digital gain 32kHz - 92 - dB 44.1kHz - 92 - dB 48kHz - 92 - dB Fsample 8kHz - 0.004 - % 48kHz - 0.008 - % Digital gain resolution = 1/32 -24 Pre-amplifier setting = 0dB, 9dB, 21dB or 30dB Analogue setting = -3dB to 12dB in 3dB steps Analogue gain Stereo separation (crosstalk) - 21.
Bluetooth Audio Module 48kHz Digital Gain 16Ω Digital Gain Resolution = 1/32 Analogue Gain Analogue Gain Resolution = 3dB Stereo separation (crosstalk) - 0.004 - % -24 - 21.5 dB -21 - 0 dB - -88 - dB Table 7: Digital to Analogue Converter 5. Pinout and Terminal Description 5.1.
Bluetooth Audio Module internal pull-down Bi-directional with weak internal pull-down CMOS output, tri-state, with weak internal pulldown 10 PCM_SYNC 11 PCM_OUT 12 RESETB 13 UART_CTS 14 UART_RTS 15 UART_RX 16 UART_TX 17 USB_D+ Bi-directional USB data plus with selectable internal 1.
Bluetooth Audio Module internal pull-up/down 29 PIO5 30 PIO14 31 PIO4 32 VDD_3V3 33 GND 34 VDD_CHG 35 QSPI_FALSH_IO3 36 37 38 39 Bi-directional with programmable strength internal pull-up/down Bi-directional with programmable strength internal pull-up/down Bi-directional with programmable strength internal pull-up/down QSPI_FLASH_IO1 41 QSPI_SRAM_CLK 42 QSPI_SRAM_CS Programmable input/output line Programmable input/output line Power Supply +2.7V- +3.
Bluetooth Audio Module 52 SPK_LP 53 GND Analogue Speaker output positive, left Ground Ground Table 8：PIN Terminal Description 6. Physical Interfaces 6.1. Power Supply - The module DC3.3V power input. Power supply pin connection capacitor to chip and pin as far as possible close Capacitor decouples power to the chip Capacitor prevents noise coupling back to power plane. . Figure 2：Power Supply PCB Design 6.2.
Bluetooth Audio Module UART_RX UART_TX UART_RTS UART_CTS SPI_MOSI SPI_CLK SPI_CSB SPI_MISO RESET PIOs PCM_IN PCM_CLK PCM_SYNC PCM_OUT QSPI_SRAM_CS QSPI_FLASH_CS QSPI_SRAM_CLK QSPI_FLASH_CLK Strong PU Weak PU Weak PU Weak PD Weak PD Weak PD Strong PU Weak PD Strong PU Weak PD Weak PD Weak PD Weak PD Weak PD Strong PU Strong PU Strong PD Strong PD Table 9: Pin Status on Reset 6.3. PIO EH-MB18 has a total of 13digital programmable I/O terminals. They are powered from VDD .
Bluetooth Audio Module The UART CTS and RTS signals can be used to implement RS232 hardware flow control where both are active low indicators. Parameter Baud Rate Possible Values Minimum Maximum Flow Control Parity Number of Stop Bits Bits per Byte 1200 baud (≤2%Error) 9600 baud (≤1%Error) 3M baud (≤1%Error) RTS/CTS or None None, Odd or Even 1 or 2 8 Table 10: Possible UART Settings Figure 3：Connection To Host device 6.7. I2C Master PIO6, PIO7 and PIO8 can be used to form a master I2C interface.
Bluetooth Audio Module 2 Figure 4 : Example EEPROM Connection with I C Interface 6.8. Apple iOS CP reference design The figures below give an indicative overview of what the hardware concept looks like. A specific MFI co-processor layout is available for licensed MFI developers from the MFI program. Figure 5 : Apple Co-processor 2.0C Ehong Technology Co.
Bluetooth Audio Module Figure 6 : Apple Co-processor 2.0B 6.9. Digital Audio Interfaces The audio interface circuit consists of: ■ Stereo/Dual-mono audio codec ■ Dual audio inputs and outputs ■ 6 digital MEMS microphone inputs ■ A configurable PCM, I²S or SPDIF interface Figure 2 outlines the functional blocks of the interface. The codec supports stereo playback and recording of audio signals at multiple sample rates with a resolution of 16-bit.
Bluetooth Audio Module Figure 7 : Audio Interface The interface for the digital audio bus shares the same pins as the PCM codec interface described in Table 11, which means each of the audio buses are mutually exclusive in their usage. Table 11 lists these alternative functions.
Bluetooth Audio Module It supports 13-bit or 16-bit linear, 8-bit u-law or A-law companded sample formats and can receive and transmit on any selection of three of the first four slots following PCM_SYNC.
Bluetooth Audio Module Figure 8 : Digital Audio Interface Modes Symbol Parameter Min Typical Max Unit - SCK Frequency - WS Frequency tch SCK high time tcl topd SCK low time tssu WS to SCK set up time 80 80 20 - 6.2 96 20 - MHz kHz ns ns ns ns tsh WS to SCK hold time 20 - - ns tisu SD_IN to SCK set-up time tih SD_IN to SCK hold time 20 20 - - ns ns SCK to SD_OUT delay Ehong Technology Co.
Bluetooth Audio Module Table 12 : Digital Audio Interface Slave Timing Figure 9 : Digital Audio Interface Slave Timing Symbol Parameter Min Typical Max Unit - SCK Frequency - WS Frequency topd SCK to SD_OUT delay tspd SCK to WS delay tisu SD_IN to SCK set-up time tih SD_IN to SCK hold time 20 10 - MHz kHz ns ns ns ns Table 13 : Digital Audio Interface Master Timing Figure 10 : Digital Audio Interface Master Timing Ehong Technology Co., Ltd 6.
Bluetooth Audio Module 6.9.3. IEC 60958 Interface (SPDIF) The IEC 60958 interface is a digital audio interface that uses bi-phase coding to minimise the DC content of the transmitted signal and allows the receiver to decode the clock information from the transmitted signal. The IEC 60958 specification is based on the 2 industry standards: ■ AES/EBU ■ Sony and Philips interface specification SPDIF The interface is compatible with IEC 60958-1, IEC 60958-3 and IEC 60958-4.
Bluetooth Audio Module 6.10. Microphone input The module contains 2 independent low-noise microphone bias generators. The microphone bias generators are recommended for biasing electret condensor microphones. Figure 9.6 shows a biasing circuit for microphones with a sensitivity between about ‑ 40 to ‑ 60dB (0dB = 1V/Pa): Where: ■ The microphone bias generators derives their power from VBAT or VOUT_3V3 \ and requires no capacitor on its output.
Bluetooth Audio Module The microphone bias characteristics include: ■ Power supply: ■ CSR8670 BGA microphone supply is VBAT (via SMP_VBAT) or VOUT_3V3 (via SMPS_3V3) ■ Minimum input voltage = Output voltage + drop-out voltage ■ Maximum input voltage is 4.25V ■ Drop-out voltage: ■ 300mV maximum ■ Output voltage: ■ 1.8V or 2.6V ■ Tolerance 90% to 110% ■ Output current: ■ 70μA to 2.8mA ■ No load capacitor required 6.11.
Bluetooth Audio Module The module has an internal USB pull-up resistor. This pulls the USB_DP pin weakly high when module is ready to enumerate. It signals to the USB master that it is a full speed (12Mbit/s) USB device. Figure 15: USB Connections Identifier Value Function Rs 27Ω Nominal Impedance matching to USB cable Table 14: USB Interface Component Values Note: USB_ON is only used when the firmware need an input to detect if USB is connected and the USB function shall be enabled.
Bluetooth Audio Module 7. EH-MB18 Reference Design Figure 16: Reference Design Ehong Technology Co.
Bluetooth Audio Module 8. Mechanical and PCB Footprint Characteristics Figure 17: Recommended PCB Mounting Pattern (Unit: mm, Deviation:0.02mm)TOP View Ehong Technology Co.
Bluetooth Audio Module 9. RF Layout Guidelines EH-MB18 RF design to ensure enough clearance area of antenna, area length is 1.6 times of antenna length, area width is 4 times of antenna width, the bigger the better if the space allows. Module antenna clearance area size, as follows. Figure 18: Clearance Area of Antenna Ehong Technology Co.
Bluetooth Audio Module 10. Reflow Profile The soldering profile depends on various parameters necessitating a set up for each application. The data here is given only for guidance on solder reflow. ℃ 250 217 210 A 25 0 B 1 2 C 3 D 4 E 5 6 min Figure 19: Recommended Reflow Profile Pre-heat zone (A) — This zone raises the temperature at a controlled rate, typically 0.5 – 2 C/s. The purpose of this zone is to preheat the PCB board and components to 120 ~ 150 C.
Bluetooth Audio Module 11. Contact Information Sales: sales@ehlink.com.cn Technical support: support@ehlink.com.cn Phone: +86 21 64769993 Fax: +86 21 64765833 Street address: Rom1505, Blk 1st ,No.833 South Hong mei Rd ,Ming hang district shanghai Ehong Technology Co.
NOTE: This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications.
