FAA TSO-C71 REGULATED DC TO DC CONVERTER

LIGHT DIMMER WITH EXTERNAL VOLTAGE CONTROL 

The LT-53, LT-73 and LT-103 are pulse width-modulated DC to DC converters that provide regulated power.

These converters transform an unregulated 28 VDC to a regulated and adjustable DC output via a remote control voltage; 0 to 5 VDC typical or 0 to 28 VDC.

The LT-Series are used to control the light intensity of incandescent bulbs in aircraft instrument lighting when voltage control is required.

Features:

  • State of the art design for regulation and positive logic for output overvoltage protection.
  • Other voltage control range is available.
  • The Model LT-Series is serviceable, small and lightweight (33 watts per pound and 1.7 watts per cubic inch).
  • Maximum output voltage is adjustable with an internal trim pot.
  • Designed to meet various applicable portions MIL-STD 704 notice 3, MIL-STD-202 and MIL-T-5422F class 1A.
Specifications:
Input Voltage: 28 VDC nom., 20  to  40 VDC.
Output Voltage: Adjustable with external voltage from 0 to 5 VDC.
Regulation: 2% for line, 2% load and 2% temperature.
Output Ripple: 25 mVp-p.
Protection (Overload): Input and output current pulse when overload exceeds approximately 125% of rating.
Protection (Overvoltage): Output voltage is limited to approximately 125% of rating eventhough remote control rheostat opens or shorts, or internal failure occurs.
Temperature: -55°C to +71°C (sufficient cooling required @ +71°C ambient)
Altitude: 55,000 Feet.
Size: 2.3" H x 2. 3" W x 5.8" L.
5.7 cm H x 5.7 cm W x 14.6 cm L
Weight: 1.5 lbs. (683 grams).
Compliance: FAA TSO-C71

 

Characteristics LT-53 LT-73

LT-103

Max VA Rating 50 70 100
Input Voltage (VDC) 20 to 40 20 to 40 20 to 40
Input Current (ADC)
  • @20VDC In
  • @28VDC In

 

3.7
2.5

 

4.0
3.2

 

5.8
4.2

Output Voltage (VDC) 0 to 5 0 to 12 0 to 28
Output Current (ADC) 10 5.8 3.6
Efficiency 73 78 84

 

Pin Descriptions:

PIN NO. DESCRIPTION REMARKS
A +28 VDC input 20 to 40 VDC
B Common Ground Input/output return
C + VDC Output Adjustable DC Output
D Remote Control 0 to 5 VDC
E Remote Control 0 to 28 VDC

Connectors:

Model Mating Plug Receptacle
LT-53 KPT-06A-14-5S PT-02E-14-5P
LT-73 MS3106A14S-5S-X MS3102A14S-5P-X
LT-103 MS3106A14S-5S MS3102A14S-5P

 

Outline Drawing | External WiringInput vs Output Voltage