Texas Instruments TCM4300 - Manual (Page 15)

1–7
1.4 Terminal Functions (Continued)
TERMINAL
I/O DESCRIPTION
NAME NO.
I/O DESCRIPTION
SCEN 94 O Speech CODEC enable. A high out from SCEN can enable the speech CODEC.
SINT 79 O Sample interrupt. SINT is active low. In the analog mode, SINT occurs at 40 kHz; in the
digital mode, SINT occurs at 48.6 kHz.
SYNCLK 32 O Synthesizer clock. SYNCLK clocks the serial data stream.
SYNDTA 31 O Synthesizer serial-data. SYNDTA provides the serial bit stream output.
SYNLE0 28 O Synthesizer 0, 1, and 2 latch enables. An active high on SYNLE0, SYNLE1, and
SYNLE2 i di
t th t th l t h i bl d
SYNLE1 29 O
y g
SYNLE2 indicates that the latch is enabled.
SYNLE2 30 O
SYNOL 27 I Synthesizer out-of-lock. An active high at SYNOL indicates a synthesizer is not locked.
TXEN 23 O Transmit power enable. An active high output from TXEN can be used to enable various
system transmitter-circuit devices.
TXIN 18 O In-phase differential negative baseband transmit. The negative component of the
differential baseband transmit signal is output from TXIN.
TXIP 17 O In-phase differential positive baseband transmit. The positive component of the
differential baseband transmit signal is output from TXIP.
TXONIND 24 I Transmit on indicator. A signal is applied to TXONIND to indicate that power is applied
to the power amplifier.
TXQN 21 O Quadrature differential negative baseband transmit. The negative component of the
quadrature differential transmit signal is output from TXQN.
TXQP 20 O Quadrature differential positive baseband transmit. The positive component of the
quadrature differential transmit signal is output from TXQP.
VCM 15 I Voltage common mode. VCM establishes the dc operating point for transmit outputs and
can be tied to VHR.
VHR 14 O Voltage half-rail. The voltage level at VHR is approximately 0.5
×
AVDD. VHR
establishes the dc operating point for receive inputs.
VSS 13, 97 — Substrate ground
XTAL 66 I Crystal input. A crystal connected between XTAL and MCLIN forms an oscillator circuit.