Rainbow Electronics ISD14B20 - Manual (Page 15)

ISD14B20
Publication Release Date: October 9, 2007
- 15 - Revision 0
• When R
OSC
resistor value is changed during playback, the tone of a recorded message will alter either
faster or slower.
• If the ground side of R
OSC
resistor is floated or tied to V
CC
, then the current operation will be freezed.
• The operation will resume when the resistor is connected back to ground.
5.3.2. LED Operation
• LED turns on during recording. Also, LED pulses Low at the end of message. The Low period must
be sufficiently greater than debounce time.
5.3.3. Feed-Through mode Operation
• As FT is held Low, the Mic+ pin will be reconfigured as AnaIn input then the AnaIn signal will be
transmitted to the speaker outputs. Under this mode, Mic- pin is not used (must be floated).
• After FT is enabled, If REC is triggered, then AnaIn signal will be recorded into memory while the
Feed-Through path remains on.
• If FT is already enabled, activating either PlayE or PlayL will first disable the FT path then play the
recorded message. Once playback completes, FT path will be resumed.
• During an operation, activating the FT pin is not allowed.
5.3.4. Power-On Playback Operation
• If PlayE is kept at Low during power turns on, the device plays message once, then powers down.
• If PlayL is held at Low during power turns on and constantly maintained at Low, the device will play the
message repeatedly, with insignificant dead time between messages regardless of sampling
frequencies. This status will sustain unless power is turned off or
PlayL somehow returns to High.
5.3.5. Automatic Single Message Playback
• If LED is connected to PlayE , once PlayE is triggered, then the device plays message repeatedly
without power down between the looping playback. However, if PlayE is triggered again during
playback, then playback will stop.
5.3.6. Power is interrupted Abruptly
• During the device is in operation, it is strongly recommended that the supply power cannot be
interrupted. Otherwise, it may cause the device to become malfunctioning.