3 Electrical Characteristics

The following table provides the absolute maximum specification conditions of the BM20/23 module.

Table 3-1. Absolute Maximum Specification
Symbol Parameter Min. Max. Unit
BAT_IN Input voltage for battery 0 4.3 V
ADAP_IN Input voltage for adapter 0 7.0 V
TSTORE Storage temperature -65 +150 ºC
TOPERATION Operation temperature -20 +70 ºC

The following table provides the recommended operating condition of the BM20/23 module.

Table 3-2. Recommended Operating Condition
Symbol Parameter Min. Typical Max. Unit
BAT_IN Input voltage for battery 3 3.7 4.2 V
ADAP_IN Input voltage for adapter 4.5 5 5.5 V
TOPERATION Operation temperature -20 +25 +70 ºC
Note: The absolute and recommended operating condition tables reflect typical usage for device.
CAUTION: Stresses listed under Absolute Maximum Ratings cause permanent damage to the device. This is a stress rating only. The functional operation of the device at those or any other conditions and those indicated in the operation listings of this specification, is not implied. Exposure to maximum rating conditions for extended periods affects the device reliability.

The parameters of the I/O and reset level are shown in the following table.

Table 3-3. I/O and Reset Level
Parameter Min. Typ. Max. Units
I/O supply voltage (VDD_IO) 2.7 — 3.3 V
I/O Voltage Levels
VIL input logic levels low ‐0.3 — 0.8 V
VIH input logic levels high 2.0 — 3.6 V
VOL output logic levels low — — 0.4 V
VOH output logic levels high 2.4 — — V
RESET
VTH,RES threshold voltage — 1.6 — V
Note:
  1. VDD_IO voltage is programmable by EEPROM parameters.
  2. These parameters are characterized but not tested in manufacturing.

The parameters of the battery charger are shown in the following table.

Table 3-4. Battery Charger
Parameter Min Typical Max Unit
ADAP_IN input voltage 4.5 5.0 5.5 V
Supply current to charger only — 3 4.5 mA

Maximum battery

Fast charge current

Note: ENX2 = 0

Headroom > 0.7V

(ADAP_IN = 5V)		 170 200 240 mA

Headroom = 0.3V

(ADAP_IN = 4.5V)		 160 180 240 mA

Maximum battery

Fast charge current

Note: ENX2 = 1

Headroom > 0.7V

(ADAP_IN = 5V)		 330 350 420 mA

Headroom = 0.3V

(ADAP_IN = 4.5V)		 180 220 270 mA
Trickle charge voltage threshold — 3 — V

Battery charge termination current,

(% of fast charge current)		 — 10 — %
Note:
  1. Headroom = VADAP_IN – VBAT
  2. ENX2 is not allowed to be enabled, when VADAP_IN – VBAT > 2V
  3. These parameters are characterized but not tested in manufacturing

The parameters of the LED driver are shown in the following table.

Table 3-5. LED driver
Parameter Min Typical Max Unit
Open-drain voltage — — 3.6 V
Programmable current range 0 — 5.25 mA
Intensity control — 16 — Step
Current step — 0.35 — mA
Power down open-drain current — — 1 μA
Shutdown current — — 1 μA
Note:
  1. Test condition: SAR_VDD = 1.8V, temperature = 25 ºC.
  2. These parameters are characterized but not tested in manufacturing.

The parameters of the audio Codec ADC are provided in the following table.

T = 25ºC, Vdd = 3.0V, 1 kHz sine wave input, Bandwidth = 20 Hz to 20 kHz.

Table 3-6. Audio Codec ADC
Parameter (Condition) Min. Typ. Max. Unit
Resolution — — 16 Bits
Output sample rate 8 — 48 kHz

Signal-to-Noise Ratio Note: 1

(SNR at MIC or Line-in mode) 		88 — dB
Digital gain -54 4.85 dB
Digital gain resolution — 2 to 6 — dB
MIC boost gain — 20 — dB
Analog gain — — 60 dB
Analog gain resolution — 2.0 — dB
Input full-scale at maximum gain (differential) — 4 — mV rms
Input full-scale at minimum gain (differential) — 800 — mV rms
3 dB bandwidth — 20 — kHz
Microphone mode (input impedance) — 24 — kOhm
THD+N (microphone input) at 30 mV/rms input — 0.02 — %
Note:
  1. fin = 1 kHz, B/W = 20 Hz to 20 kHz, A-weighted, THD+N < 1%, 150 mVpp input.
  2. These parameters are characterized but not tested in manufacturing.

The parameters of the audio Codec DAC are provided in the following table.

T = 25℃, Vdd = 3.0V, 1 kHz sine wave input, Bandwidth = 20 Hz to 20 kHz

Table 3-7. Audio Codec DAC
Parameter Min. Typ. Max. Unit
Over-sampling rate — 128 — fs
Resolution 16 — 20 Bits
Output sample rate 8 — 48 kHz

Signal-to-Noise Ratio (Note: 1)

(SNR at Capless mode) for 48 kHz		 — 96 — dB

Signal-to-Noise Ratio (Note: 1)

(SNR at Single-Ended mode) for 48 kHz		 — 98 — dB
Digital gain -54 — 4.85 dB
Digital gain resolution — 2 to 6 — dB
Analog gain -28 — 3 dB
Analog gain resolution — 1 — dB
Output voltage full-scale swing (AVDD = 2.8V) (Note: 3) — 742.5 — mV/rms
Maximum output power (16 Ohm load) — 34.5 — mW
Maximum output power (32 Ohm load) — 17.2 — mW
Allowed load (Resistive) 8 16 O.C. Ω
Allowed load (Capacitive) — — 500 pF
THD+N (16 Ohm load) — — 0.05 %
Signal-to-Noise Ratio (SNR at 16 Ohm load) — — 96 dB
Note:
  1. fin = 1 kHz, B/W = 20 Hz to 20 kHz, A-weighted, THD+N < 0.01%, 0 dBFS signal, Load = 100 kOhm.
  2. These parameters are characterized but not tested in manufacturing.
  3. Vdd and AVDD are generated by internal LDO.

The parameters of the transmitter section for BDR and EDR are shown in the following table.

Test condition: VCC_RF = 1.28V, temperature = 25ºC.

Table 3-8. Transmitter section for BDR and EDR
Parameter Min. Typ. Max. Bluetooth specifications Unit
Maximum RF transmit power (BM20 — — — -6 to 4 dB
Maximum RF transmit power (BM23) — 2 — -6 to 4 —

EDR/BDR

Relative transmit power		 -4 -1.2 1 -4 to 1 dB
Note: The RF Transmit power is calibrated during production using MP Tool software and MT8852 Bluetooth Test equipment.

The parameters of the receiver section for BDR and EDR are shown in the following table.

Test condition: VCC_RF = 1.28V, temperature = 25ºC.

Table 3-9. Receiver Section for BDR and EDR
Parameters Modulation Min. Typ. Max. Bluetooth Specification Unit
Sensitivity at 0.1% BER GFSK — -90 — ≤-70 dBm
Sensitivity at 0.01% BER π/4 DQPSK — -91 — ≤-70 dBm
8DPSK — -82 — ≤-70 dBm
Note: These parameters are characterized but not tested in manufacturing.

The parameters of system current consumption of analog audio output are shown in the following table.

Test condition: BAT_IN = 3.8V, link with HTC EYE cell phone; distance between cell phone and EVB is 30 cm.

Table 3-10. System Current Consumption of Analog Audio Output
System Status Typ. Max. Unit
System off mode 2 5 µA
Standby mode 0.8 — mA
Linked mode 0.4 — mA
SCO link 7.8 — mA
A2DP link (Vp-p = 200 mV; 1k tone signal) 10.7 — mA
Note: Use BM20 EVB as a test platform.

The parameters of system current consumption of digital audio output are shown in the following table.

Test condition: BAT_IN = 3.8V, link with HTC M8 cell phone; distance between cell phone and EVB is 30 cm; I2S signal link with YAMAHA YDA174 EVB.

Table 3-11. System Current Consumption of Digital Audio Output
System status Typ Max Unit
System Off mode 2 5 µA
Standby mode 0.4 — mA
Linked mode 0.4 — mA
SCO link 9.3 — mA
A2DP link (1k tone signal) 11.7 — mA
Note: Use BM23 EVB as a test platform.