Datasheet

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LTC1385

sn1385 1385fas

3.3V Low Power

EIA/TIA-562 Transceiver

■

Operates from a Single 3.3V Supply

■

Low Supply Current: I

= 200µA

■

= 35µA in Driver Disable Mode

■

= 0.2µA in Shutdown Mode

■

ESD Protection Over ±10kV

■

Uses Small Capacitors: 0.1µF

■

Operates to 120kBaud

■

Output Overvoltage Does Not Force Current

Back into Supplies

■

EIA/TIA-562 I/O Lines Can Be Forced to ±25V

Without Damage

■

Pin Compatible with LT1180A

The LTC

1385 is an ultra-low power, 2-driver/2-receiver

EIA/TIA-562 transceiver which operates from a single

3.3V supply. The charge pump requires only four space-

saving 0.1µF capacitors.

The transceiver operates in one of three modes: Normal,

Driver Disable or Shutdown. In the Normal mode, I

only 200µA in the unloaded condition. In the Driver Disable

mode, the charge pump is turned off, the driver outputs

are forced into three-state, both receivers are kept active,

and I

drops to 35µA. In the Shutdown mode, everything

is turned off and I

drops to 0.2µA.

The LTC1385 is fully compliant with all data rate and

overvoltage EIA/TIA-562 specifications. The transceiver

can operate up to 120kbaud with a 1000pF, 3kΩ load.

Both driver outputs and receiver inputs can be forced to

±25V without damage, and can survive multiple ±10kV

ESD strikes.

■

Notebook Computers

■

Palmtop Computers

Quiescent and Shutdown Supply Current

vs Temperature

2-Drivers/2-Receivers with Shutdown

and Driver Disable

TEMPERATURE (°C)

QUIESCENT CURRENT (µA)

600

500

400

300

200

100

LTC1385 • TA02

800

1.2

1.0

0.8

0.6

0.4

0.2

SHUTDOWN CURRENT (µA)

QUIESCENT

CURRENT

SHUTDOWN

CURRENT

TEST CONDITION: V

= 3.3V

–20

FEATURES

DESCRIPTIO

APPLICATIO S

TYPICAL APPLICATIO

, LTC and LT are registered trademarks of Linear Technology Corporation.

LTC1385 • TA01

0.1µF

LTC1385

DRIVER DISABLE

LOGIC INPUT

LOGIC OUTPUT

ON/OFF

562 OUTPUT

= 3.3V

562 OUTPUT

562 INPUT

300k

Summary of content (8 pages)

PAGE 1
LTC1385 3.3V Low Power EIA/TIA-562 Transceiver U FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ DESCRIPTIO The LTC®1385 is an ultra-low power, 2-driver/2-receiver EIA / TIA-562 transceiver which operates from a single 3.3V supply. The charge pump requires only four spacesaving 0.1µF capacitors. Operates from a Single 3.3V Supply Low Supply Current: ICC = 200µA ICC = 35µA in Driver Disable Mode ICC = 0.2µA in Shutdown Mode ESD Protection Over ±10kV Uses Small Capacitors: 0.
PAGE 2
LTC1385 W W W AXI U U ABSOLUTE RATI GS Supply Voltage (VCC) ................................................ 5V Input Voltage Driver ....................................... – 0.3V to V CC + 0.3V Receiver ............................................... – 25V to 25V Digital Input ............................... – 0.3V to VCC + 0.3V Output Voltage Driver .................................................... – 25V to 25V Receiver .................................... – 0.3V to VCC + 0.
PAGE 3
LTC1385 DC ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range. VCC = 3.3V, C1 = C2 = C3 = C4 = 0.1µF, VON/OFF = VCC, Driver Disable = VCC, unless noted.
PAGE 4
LTC1385 U W TYPICAL PERFOR A CE CHARACTERISTICS Driver Output Voltage vs Temperature Receiver Input Thresholds vs Temperature 5 OUTPUT HIGH VCC = 3.3V 2 1 ALL DRIVERS WITH LOAD RL = 3k 0 –1 –2 OUTPUT LOW VCC = 3.3V –3 –4 10 40 30 20 50 TEMPERATURE (°C) 1.8 VTH+ 1.6 1.4 VTH– 60 1.0 70 10 5 0 0 10 40 30 50 20 TEMPERATURE (˚C) LTC1385 • TPC01 60 70 0 Driver Leakage in Shutdown vs Temperature 4.0 40 16 LEAKAGE CURRENT (µA) 2.5 1 DRIVER LOADED RL = 3k 2.0 1.5 1.
PAGE 5
LTC1385 U U U PI FU CTIO S VCC: 3.3V Input Supply Pin. This pin should be decoupled with a 0.1µF ceramic capacitor. GND: Ground Pin. ON/OFF: TTL/CMOS Compatible Shutdown Pin. A logic low puts the device in the Shutdown mode independent of the Driver Disable pin. The supply current drops to 0.2µA and all driver and receiver outputs are forced into three-state. DRIVER DISABLE: TTL/CMOS Compatible Input Pin.
PAGE 6
LTC1385 TEST CIRCUITS Receiver Timing Test Load Driver Timing Test Load DRIVER INPUT RX OUTPUT DRIVER OUTPUT RX INPUT DRIVER 51pF RX 51pF 3k 1385 F04 1385 F03 ESD Test Circuit 17 2 0.1µF LTC1385 4 LOGIC INPUT 6 VCC LOGIC OUTPUT LOGIC OUTPUT 0.1µF 300k 15 12 S VCC LOGIC INPUT 11 13 0.1µF 562 OUTPUT 300k 8 S 14 S 5k 10 S 5k ON/OFF VCC 7 5 0.
PAGE 7
LTC1385 U PACKAGE DESCRIPTIO G Package 20-Lead Plastic SSOP (5.3mm) (Reference LTC DWG # 05-08-1640) 6.90 – 7.50* (.272 – .295 ) 20 19 18 17 16 15 14 13 12 11 1.25 ±0.12 7.8 – 8.2 5.3 – 5.7 7.40 – 8.20 (.291 – .323) 0.42 ±0.03 0.65 BSC RECOMMENDED SOLDER PAD LAYOUT 1 2 3 4 5 6 7 8 9 10 5.00 – 5.60** (.197 – .221) 2.0 (.079) 0° – 8° 0.65 (.0256) BSC 0.55 – 0.95 (.022 – .037) 0.09 – 0.25 (.0035 – .010) 0.05 (.002) 0.22 – 0.38 (.009 – .015) NOTE: 1.
PAGE 8
LTC1385 U PACKAGE DESCRIPTIO SW Package 18-Lead Plastic Small Outline (Wide .300 Inch) (Reference LTC DWG # 05-08-1620) .050 BSC .045 ±.005 .030 ±.005 TYP .447 – .463 (11.354 – 11.760) NOTE 4 N 18 17 16 15 14 13 12 11 10 N .325 ±.005 .420 MIN .394 – .419 (10.007 – 10.643) NOTE 3 1 2 3 N/2 N/2 RECOMMENDED SOLDER PAD LAYOUT .005 (0.127) RAD MIN .291 – .299 (7.391 – 7.595) NOTE 4 .010 – .029 × 45° (0.254 – 0.737) .009 – .013 (0.229 – 0.330) NOTE: 1.