Two digital voltmeters

Procedure

The Oceanside board is fully assembled and tested. Follow the steps below to verify board operation.

1. Place the shunt on jumper JU1 to the 1-2 position.

2. Connect the positive terminal of the power supply to the VIN connector.

3. Connect the negative terminal of the power supply to the GND1 connector.

4. Connect the positive terminal of the first voltmeter to the +15V connector.

5. Connect the negative terminal of the first voltmeter to the GND2 connector.

6. Connect the positive terminal of the second voltmeter to the -15V connector.

7. Connect the negative terminal of the second voltmeter to the GND2 connector.

8. Turn on the power supply.

9. Use the respective voltmeters to measure the corresponding positive and negative output voltages.

Lab Measurements

The Oceanside design was tested with two pairs of output voltage rails: ±15V and ±12V. Other voltage rails can

be achieved by modifying the resistor value ratios of R3/R4, R7/R9, and R8/R10. Equal loads on both rails were

used when testing the Oceanside design. Table 1 shows the maximum load for various setups. The maximum

load is recorded when the output voltage drops to 1% less than the designed output voltage. The power

efficiency (as shown in Figures 2 to 8) is calculated with the sum of the output power on both rails divided by

the input power.

For asymmetrical load applications, the maximum load can be larger for one rail and less for the other rail. To

achieve a larger maximum load, the user can increase the output voltage of the step-up controller, but the

efficiency will decrease due to the higher voltage drop across the LDO.

Table 1. Maximum Load for Test Setups

Input

Voltage (V)

Output

Rail (V)

Maximum Load (Equal Loads Applied to

Both Rails) (mA)

Efficiency at Maximum

Load (%)

3.3

±15

65

78

5

±15

70

79

12

±15

85

83

15

±15

90

86

3.3

±12

75

77

5

±12

80

78

12

±12

100

83

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