ml2500b Oki Optical Components, ml2500b Datasheet - Page 23

• Manufacturer Part Number: ml2500b
• Description: Analog-storage Single-chip Record/playback With Bit-cell Flash Memory
• Manufacturer: Oki Optical Components

LOUT Output Voltage Range Allowance
The LSI has a built-in OP amplifier to amplify incoming analog source signal. The inverting input pin to the OP
amplifier (LIN pin) and the output pin from the OP amplifier (LOUT pin) are available. The non-inverting input is
internally connected to the Reference Voltage (Signal Ground 1.35 V).
As shown in the above wiring sample, the ML2500B is configured so that recording signal can be created through
inverting amplifying circuit configured by connecting external resistors, R1 and R2, to the LIN pin and the LOUT
pin. The LOUT pin's output voltage (VLOUT) becomes actual recording voltage, and thus is input to the LPF
within the LSI.
It is recommended to adjust the amplifying rate so that the dynamic range of the VLOUT voltage will be from 0.5
to 2.2 V for voice input and will be ±0.5 V with respect to the SG voltage for beep.
If the VLOUT voltage exceeds the recommended voltage range, then the LSI’s internal LPF’s output would be
clipped waveform, resulting in degradation of memory reliability.
States of Output Pins during Power Down
OKI Semiconductor
AOUT
MON
Pins
DO
SG
States of output pins during power down
R1
High impedance (Hi-Z)
SG (Signal GND) ≅ 1.35 V
LIN Pin
GND level
GND level
“L” level
–
+
R2
LOUT Pin
2.2 V
0.5 V
Connect to LPF
Voice Waveform
LOUT Output Signal (VLOUT)
Beep
FEDL2500BFULL-02
0.5 V
SG Voltage
0.5 V
ML2500BTA
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