Building Block Solutions for MCP1501 Voltage References FAQs

The BB89X25A MCP1501 Voltage Reference BBS Kit is a modular evaluation platform containing several analog and mixed signal devices configured in separate BBS boards. It provides 10 different high-precision voltage reference devices, allowing users to evaluate and implement solutions in system-level applications. Each board can be used independently or in combination with other boards.

The kit includes 10 MCP1501 High Precision Voltage Reference BBS boards with the following output voltages:

• MCP1501-10 – 1.024V output
• MCP1501-12 – 1.25V output
• MCP1501-18 – 1.8V output
• MCP1501-20 – 2.048V output
• MCP1501-25 – 2.5V output
• MCP1501-30 – 3.0V output
• MCP1501-33 – 3.3V output
• MCP1501-40 – 4.096V output
• MCP1501-45 – 4.5V output
• MCP1501-50 – 5.0V output

The boards come fully populated with Surface-Mount Device (SMD) components. For evaluation, you will need:

• Header pins (not included) for connectivity
• An external laboratory power supply
• An oscilloscope for data acquisition and monitoring

Depending on the specific application, some or all these components may be required in combination.

The MCP1501 BBS Kit is designed for the following applications and use cases, including but not limited to:

• Rapid prototyping and evaluation of precision voltage reference solutions
• Battery Management Systems (BMS) – both automotive and industrial, leveraging the AEC-Q100 automotive-qualified MCP1501 family
• Analog-to-Digital Converter (ADC) reference voltage supply – providing a precise, low-noise reference for our ADC families such as the MCP3201 (12-bit) and MCP33131 Successive Approximation Register (SAR) ADC
• Negative voltage reference generation using an inverting amplifier configuration with the MCP6061
• Any application requiring a stable, buffered, high-precision reference voltage

The BB89X25A MCP1501 BBS Kit speeds up prototyping because it provides a pre-configured set of 10 diverse, precision voltage reference boards that you can test, compare and integrate immediately—no additional design or assembly required. The modular format allows users to seamlessly integrate individual boards into existing systems or configure multiple boards for diverse application requirements.

Select the board whose output voltage matches the reference voltage required by your system:

• For 1.8V AVDD supply on the MCP33131-10 SAR ADC, use MCP1501-18
• For a standard 2.5V precision reference, use MCP1501-25
• For a 4.096V reference (convenient for 12-bit ADCs with 1 mV/LSB scaling), use MCP1501-40
• For a 5.0V reference, use MCP1501-50
• For a negative voltage reference, use MCP1501-25 with an external MCP6061 op-amp inverter circuit

The power-up procedure for each MCP1501 BBS board is:

• Connect the header pins (not included) to the 4-pin connector (J) on your selected board
• Apply power to the VDD pin using the correct minimum supply voltage for your chosen variant (see table below) — the maximum for all variants is 5.5V
• It is recommended to connect a 0.1 µF decoupling capacitor very close to the VDD pin — this is already populated on each BBS board (C×1)
• The SHDN pin (pin 4 on SOT-23) is active low — the device is active when SHDN is held high and shuts down when pulled low. Allow the device to fully power up before using the SHDN pin
• Monitor the VOUT pin with a voltmeter — output should be close to the nominal reference voltage for the selected variant
• A 1000 pF output capacitor is already populated on each board (C×2) for noise filtering; larger capacitive loads up to 10 nF may be used without a series resistor

IMPORTANT: Each variant requires a different minimum VDD. Applying insufficient supply voltage will prevent correct output. Refer to the table below (from MCP1501 datasheet Table 2-1):

Each MCP1501 BBS board outputs a high-precision, buffered reference voltage capable of sinking and sourcing 20 mA of current (±20 mA, TA = +25°C, per datasheet Table 2-1). The absolute maximum output current rating is 30 mA, however sustained operation at ±20 mA is the specified operating limit. This makes the boards suitable not only as references but also as low-current supply rails for other components in a system.

 A negative voltage reference can be generated using any device in the MCP1501 family. The voltage inversion is implemented externally using an MCP6061 op-amp and two equal resistors (10 kΩ, 0.1%). The output of the MCP1501 drives R1, which connects to the inverting input of the MCP6061 amplifier. Since the non-inverting input is biased to ground, the current through R1 also flows through the feedback resistor R2, producing a negative output equal in magnitude to the selected reference voltage. For example, using the MCP1501-25 produces a 2.5V output; using the MCP1501-40 produces a 4.096V output. A 5V supply is required for the MCP6061 in this configuration.

 The MCP1501 product family was designed to provide a precise, low-noise voltage reference for our ADC families. Connect the OUT pin of the selected MCP1501 BBS board to the VREF pin of your ADC. A typical configuration pairs the MCP1501-25 with the MCP3201 12-bit ADC using a 50Ω series resistor between the reference output and the ADC VREF pin, with a 1 nF and a 2.2 µF capacitor at the MCP1501 output and a 10 µF reservoir capacitor at the ADC VREF pin. The 10 µF capacitor is particularly important for SAR ADCs which draw charge-kick currents during conversion. See Figure 2-6 of the user guide and Figure 5-4 of the MCP1501 datasheet (DS20005474) for the complete recommended circuit.