OPA1677DBVT datasheet(23/52 Pages) TI

23 / 52 page

8.2.2 Phono Preamplifier for Moving Magnet Cartridges

The noise and distortion performance of the OPA167x family of amplifiers is exceptional in applications with high

source impedances, which makes these devices a viable choice in preamplifier circuits for moving magnet (MM)

phono cartridges. Figure 8-4 shows a preamplifier circuit for MM cartridges with 40 dB of gain at 1 kHz.

VOUT

V+

V±

15 V

-15 V

½ OPA1678

118 k

10 k

27 nF

7.5 nF

127

47 k

150 pF

100 F

100

100 F

100 k

MM Phono Input

Output

Figure 8-4. Phono Preamplifier for Moving Magnet Cartridges (Single-Channel Shown)

8.2.3 Single-Supply Electret Microphone Preamplifier

The preamplifier circuit shown in Figure 8-5 operates the OPA1678 as a transimpedance amplifier that converts

the output current from the electret microphone internal JFET into a voltage. Resistor R4 determines the gain of

the circuit. Resistors R2 and R3 bias the input voltage to half the power supply voltage for proper functionality on

a single-supply.

½ OPA1678

61.9 k

0.1 F

9 V

Electret

Microphone

9 V

100 k

Output

13.7 k

2.2 F

16 pF

100 k

Figure 8-5. Single-Supply Electret Microphone Preamplifier

www.ti.com

OPA1677, OPA1678, OPA1679

SBOS855D – JANUARY 2017 – REVISED DECEMBER 2021

Submit Document Feedback

Product Folder Links: OPA1677 OPA1678 OPA1679

OPA1677DBVT Datasheet(PDF) 23 Page - Texas Instruments

OPA1677DBVT Datasheet(HTML) 23 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52

Datasheet Download

Link URL