Model Selection Guide

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Model

Number

Input

Output

Maximum

Power

(W)

Ripple &

Noise

(mV P-P, Max)

Efficiency

(%, Typ)

Package

Current

Range

Range

LDM24-14-500

7.0 - 30.0

2.0 - 28.0

300

±10

14

450

95

14 -Pin MiniDIP

LDM24-17-600

7.0 - 30.0

2.0 - 28.0

500

±10

17

450

95

14 -Pin MiniDIP

LDM24-20-700

7.0 - 30.0

2.0 - 28.0

700

±10

20

450

95

14 -Pin MiniDIP

Notes:

1. A reversed power source could damage the unit.

2. No connection should be made between input ground and the output.

3. These are step-down devices, the maximum output open voltage is

equal to the input voltage.

5. Exceeding the specified maximum output power could cause damage to the unit.

Connection Notes:

To comply with EN61000-4-5, a TVS should be installed before the input filter components. A 3.0SMCJ24A or SMCJ24A is recommended. The TVS max clamping voltage (@max peak pulse

40V. This will prevent any surge from exceeding the maximum input of the driver (40 VDC). Exceeding the maximum input rating could damage the driver.

Connection Notes:

This is a distributed (or two-stage) AC connection. In this configuration, the AC line in (85 to 264 VAC) is connected to the MPM-20S-24EPB, a compact 20W AC/DC

power supply. The MPM-20S-24EPB provides a tightly regulated 24 VDC output at 833 mA. The 24 VDC output powers the LED driver.

The two stage approach can simplify the safety approval process (most AC/DC power supplies on the market are approved to EN 60950) and may increase design flex-

ibility. Besides the output voltage/current ratings, other specifications to consider when selecting the input AC/DC supply might include input range, case size, efficiency,

EMI ratings and operating temperature range.

Note: The output current adjustment circuit shown in both connection diagrams is discussed on page 4.