STEVAL-CCA023V1 STMicroelectronics

STEVAL-CCA023V1 Demonstration board for low noise microphone preamplifier with 2 V bias based on the TS472 Data brief Features Low noise: 10 nV / Hz typ. equivalent input noise F=1 kHz Fully differential input/output 2.2 V to 5.5 V single supply operation Low power consumption 20 dB: 1.8 mA Fast start up time 0dB: 5 ms typ. Low distortion: 0.1% typ. 40 kHz bandwidth -3 dB and adjustable gain Active low standby mode function (1A max) Low noise 2.0 V microphone bias output Available in flip-chip ECOPACK package and STEVAL-CCA023V1 QFN24 4x4 mm ESD protection (2 kV) RoHS compliant Description The STEVAL-CCA023V1 demonstration board is designed as an evaluation platform for the TS472 low noise microphone preamplifier with 2.0 V bias and active low standby mode. The board supports customization of the testing conditions, allowing the gain of the TS472 device to be adjusted, or an electret microphone to be biased either externally or using the TS472 built- in 2.0 V bias voltage. August 2009 Doc ID 16138 Rev 1 1/4 For further information contact your local STMicroelectronics sales office. www.st.com 4 Schematic circuit STEVAL-CCA023V1 1 Schematic circuit Figure 1. Demonstration board schematic diagram 2/4 Doc ID 16138 Rev 1 Jumper J4 P10 P11 Vbias P5 VCC C1 C9 1 1 1 2 1 2 2 2 P2 Vx Vcc 100pF 100nF R9 R10 4 100k POS. OUTPUT C7 C6 3 1uF NEG. OUTPUT 100nF 2 Bias 1 C2 C8 1 2 1 2 OUTPUT C10 R6 1uF 100pF 100nF R8 100k TS472 Adapter C4 Vcc 1 2 P1 100nF 4 6 IN+ OUT+ 13 POS. INPUT 3 Jumper J2 NEG. INPUT IN- OUT- 2 8 12 1 C5 1 2 INPUT GAIN 100nF SELECT 5 P8 Gain Bias Bias 8 7 Min 6 5 Max 4 3 BIAS BYPASS R7 Bias 4 10 Bias Rgs 2 1 Gain Select C3 1uF R1 1 2 C11 R11 470k R2 1 2 P9 27k 470k 1 2 27k 3 4 R3 1 2 4k7 5 6 P6 VCC 1k 7 8 4.7k Jumper J1 1 68R 9 10 R4 2 1 2 Rgs 3 1k StandBy R5 1 2 68 Jumper J3 2 1 2 1 2 1 2 1 1 2 1 2 2 1 2 1 2 1 14 9 GND C1 3 15 STDBY C2 1 2 1 2 1 2 1