TRS3221E

Features:

` ESD Protection for RS-232 Pins
   ±15-kV Human-Body Model (HBM)
   ±8 kV (IEC 61000-4-2, Contact Discharge)
   ±15 kV (IEC 61000-4-2, Air-Gap Discharge)
` Meets or Exceeds the Requirements of TIA/EIA-232-F and ITU v.28 Standards
` Operates With 3-V to 5.5-V V<sub>CC</sub> Supply
` Operates up to 250 kbit/s
` One Driver and One Receiver
` Low Standby Current . . . 1 A Typical
` External Capacitors . . . 4 * 0.1 F
` Accepts 5-V Logic Input With 3.3-V Supply
` Alternative High-Speed Pin-Compatible Device (1 Mbit/s)
   TRSF3221E
` Auto-Powerdown Feature Automatically Disables Drivers for Power Savings


Application

· Battery-Powered, Hand-Held, and Portable  Equipment )
· PDAs and Palmtop PCs )
· Notebooks, Subnotebooks, and Laptops
· Digital Cameras
· Mobile Phones and Wireless Devices


Pinout




Specifications

			MIN	MAX	UNIT
VCC         Supply voltage range(2)			0.3	6	V
V+          output supply voltage range(2)			0.3	7	V
V-           Negative output supply voltage range(2)			0.3	-7	V
V+V   Supply voltage difference(2)				13	V
VI            Input voltage range		DIN, FORCEOFF, FORCEON, EN	0.3	6	V
		RIN	-25	25
IO   Output current range		DOUT	-13.2	13.2	V
		ROUT,INVALID	-0.3	VCC + 0.3
JA  Package thermal impedance(3) (4)	D package			82	/W
	P package			108
TJ Virtual junction temperature				150
Tstg Storage temperature range			65	150

(1) Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the
     device. These are stress ratings only, and functional operation of the device at these or any other
     conditions beyond those indicated under "recommended operating conditions" is not implied. Exposure
     to absolute-maximum-rated conditions for extended periods may affect device reliability.
(2) All voltages are with respect to the device GND terminal.
(3) Maximum power dissipation is a function of T_J(max), _JA, and T_A. The maximum allowable power dissipation
     at any allowable ambient temperature is P_D = (T_J(max) T_A)/_JA. Operating at the absolute maximum T_J
    of 150 can impact reliability.
(4) The package thermal impedance is calculated in accordance with JESD 51-7.


Description

The TRS3221E is a single driver, single receiver RS-232 solution operating from a single V_CC supply. The RS-232 pins provide IEC G1000-4-2 ESD protection. The TRS3221E meets the requirements of TIA/EIA-232-F and provides the electrical interface between an asynchronous communication controller and the serial-port connector. The charge pump and four small external capacitors allow operation from a single 3-V to 5.5-V supply. These TRS3221E operate at data signaling rates up to 250 kbit/s and a maximum of 30-V/s driver output slew rate.

Flexible control options for power management of TRS3221E are available when the serial port is inactive. The auto-powerdown feature functions when FORCEON is low and FORCEOFF is high. During this mode of operation, if the device does not sense a valid RS-232 signal on the receiver input, the driver output is disabled. If FORCEOFF is set low and EN is high, both the driver and receiver are shut off, and the supply current is reduced to 1 A. Disconnecting the serial port or turning off the peripheral drivers causes the auto-powerdown condition to occur. Auto-powerdown of TRS3221E can be disabled when FORCEON and FORCEOFF are high.

With auto-powerdown enabled, the TRS3221E is activated automatically when a valid signal is applied to the receiver input. The INVALID output notifies the user if an RS-232 signal is present at the receiver input. INVALID is high (valid data) if the receiver input voltage is greater than 2.7 V or less than 2.7 V, or has been between 0.3 V and 0.3 V for less than 30 s. INVALID is low (invalid data) if the receiver input voltage of TRS3221E  is between 0.3 V and 0.3 V for more than 30 s. Refer to Figure 5 for receiver input levels.