Power-Supply Margining Controller Simplifies Automated PCB Testing
Milpitas, Calif.--Linear Technology introduced the LTC2920, a power-supply margining controller that allows supply rails to be precisely adjusted up and down during automated PCB testing. This testing, known as "margining," is a valuable feature in high-reliability applications as it validates the correct operation of electrical components at the upper and/or lower power-supply voltage limits allowed for a given design.
The LTC2920 adjusts the power-supply voltage by sourcing or sinking current into the feedback node of the controller chip or the voltage-adjust pin of the regulator module. The versatile output stage and wide adjust-current range allow the LTC2920 to be used with most types of power supplies. The margining current is set with a single resistor channel, making it easy to design in and customize. The output current is settable over a 400:1 range, and the margin voltage precision of <0.4% guarantees proper and accurate margining tests.
The LTC2920-1 is a controller for a single supply, and it is offered in a space-saving 5-pin SOT-23, while the LTC2920-2 has two independently controllable margining channels and comes in an 8-pin MSOP. Each channel of the LTC2920-2 has its own control pin and current-setting resistor, allowing for symmetrical margining of two power supplies or asymmetrical margining of a single power supply. Pricing starts at $1.20 each for 1,000-piece quantities.
Summary of LTC2920 Features
Margin voltage precision <0.4%
400:1 current programming range
Symmetric/asymmetric high- and low-voltage margining
Single control pin per supplyHigh, Float, Low
Single current-setting resistor per supply
Wide Vcc compliance2.2 V < Vcc < 6 V
Wide output compliance0.6 V < V margin < (Vcc - 0.6 V)
Single in 5-pin SOT-23 (LTC2920-1)
Dual in 8-pin MSOP (LTC2920-2)