40
· Operates With 3-V to 5.5-V VCC Supply
· Operates up to 250 kbit/s
· One Driver and One Receiver
· Low Standby Current . . . 1
μ
A Typical
· External Capacitors . . . 4 ´ 0.1
μ
F
· Accepts 5-V Logic Input With 3.3-V Supply
· Alternative High-Speed Pin-Compatible (1 Mbit/s)
.TRSF3221E
· Auto-Powerdown Feature Automatically
Disables Drivers for Power Savings
Description
The TRS3221E is a single driver, single receiver RS-232 solution operating from a single VCC
supply. The RS-232 pins provide IEC G1000-4-2 ESD protection. The device 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 devices operate at data
signaling rates up to 250 kbit/s and a maximum of 30-V/
μ
s driver output slew rate.
Flexible control options for power management 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
μ
A. Disconnecting the serial port or turning off the
peripheral drivers causes the auto-powerdown condition to occur. Auto-powerdown can be
disabled when FORCEON and FORCEOFF are high.
With auto-powerdown enabled, the device 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
μ
s. INVALID is low (invalid data)
if the receiver input voltage is between –0.3 V and 0.3 V for more than 30
μ
s. Refer to Figure 5 for
receiver input levels.
Summary of Contents for LC-50LE442U
Page 1: ...SERVICE MANUAL LED COLOR TELEVISION MODEL LC 50LE442U ...
Page 3: ...2 ...
Page 4: ...3 ...
Page 5: ...4 CHAPTER 1 OPERATION MANUAL 1 SPECIFICATIONS ...
Page 7: ...6 50 400 400mm Metric 8 14mm Setting the TV on the wall LC 50LE442U ...
Page 44: ...43 3 WIRING DIAGRAM ...
Page 45: ...44 CHAPTER 7 PRINTED WIRING DIAGRAM 1 MAIN UNIT PRINTED WIRING BOARD TOP LC 50LE442U ...
Page 46: ...45 BOTTOM LC 50LE442U ...
Page 47: ...46 2 POWER UNIT PRINTED WIRING BOARD Top Layer ...
Page 48: ...47 Bottom Layer ...
Page 49: ...48 3 KEY UNIT PRINTED WIRING BOARD 4 IR UNIT PRINTED WIRING BOARD ...
Page 50: ...49 CHAPTER 8 SCHEMATIC DIAGRAM 1 MAIN SCHEMATIC DIAGRAM 01 System POWER ...
Page 51: ...50 02 MT5389 ...
Page 52: ...51 03 DDR3 DRAM Flash ...
Page 53: ...52 04 Peripheral IR Keypad ESD ...
Page 54: ...53 05 HDMI ...
Page 55: ...54 06 VGA RS 232 USB ...
Page 56: ...55 07 YPbPr ...
Page 57: ...56 08 Audio amp ...
Page 58: ...57 09 Headphone line out SPDIF ...
Page 59: ...58 10 LVDS 11 Tuner ...
Page 61: ...60 2 Standby Control DC DC ACD Circuit fig 8 Fig 8 Fig 9 ...
Page 68: ...67 2 CABINET PARTS LC 50LE442U ...
Page 69: ...68 ...