circuitry. It features efficient high-voltage (40 V to
1 mA.
(D)鈥?/div>
(P)
transmitting DTMF or voice frequencies. The
鈥?40擄C to 85擄C
TCM1520AD
TCM1520AP
device achieves this high input impedance with an
鈥?The D package is available taped and reeled with suffix R
on-chip series zener diode that does not conduct
added to the device type (i.e., TCM1520ADR).
until the voltage across AC INPUT (pins 1 and 8)
exceeds 8 V. When the voltage across pins 1 and
8 exceeds 18 V, the internal switch is closed, which bypasses the 6.8-V zener diode series resistor. This allows
more efficient power transfer to the load when the device is in the operating mode. In the operating mode, the
impedance of the device varies from 30 k鈩?to 7 k鈩?over the ring signal of 40 V at 16 Hz to 150 V at 68 Hz and
is reasonably independent of the output load.
In typical telephone applications, the TCM1520A is activated through the telephone line by a ring voltage of 40 V
at 16 Hz to 150 V at 68 Hz. The TCM1520A generates a signal suitable to drive an optocoupler or TTL, NMOS,
or CMOS logic. The 5-V OUTPUT can be used as a supply source for optocouplers or low-power logic. This
output is noninverting and is at a high level during ringing.
The TCM1520A incorporates lightning and transient protection that is designed to withstand lightning strikes
of 1.5-kV amplitude and 200-碌s duration and also features built-in circuitry to avoid tapping or false triggering
due to transients.
Caution. These devices have limited built-in ESD protection. The leads should be shorted together or the device placed in conductive
foam during storage or handling to prevent electrostatic damage to the MOS gates.
鈥?BIDFET 鈥?Bipolar, double-diffused, N-channel and P-channel MOS transistors on same chip. This is a patented process.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
Copyright
漏
1990, Texas Instruments Incorporated
POST OFFICE BOX 655303
POST OFFICE BOX 1443
鈥?/div>
HOUSTON, TEXAS 77251鈥?443
鈥?/div>
DALLAS, TEXAS 75265
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