Part A
MAX828EUK
オンセミコンダクター社
- Lifecycle
- Active
- Stock
- 4366 個数
- Package
- SOT-23-5
- Series
- PMIC - 電圧レギュレータ - DC/DCスイッチングレギュレータ
Replacement verdict
Not a drop-in replacement
The MAX828EUK and MAX821LUS/GG8 are not functionally interchangeable. The MAX828EUK is a switched-capacitor voltage inverter in a 5-pin SOT-23 package, while the MAX821LUS/GG8 is a microprocessor supervisory circuit in a 4-pin SOT-143 package. They differ in function, pinout, package, and electrical characteristics, so direct substitution is not possible without circuit redesign.
Different function
Different package
Different pinout
Different supply voltage
Parts at a glance
Part B
MAX821LUS/GG8
アナログ・デバイセズ社/マキシム・インテグレーテッド
- Lifecycle
- Active
- Stock
- 4512 個数
- Package
- SOT-23-4
- Series
- PMIC - スーパーバイザ
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | MAX828EUK | MAX821LUS/GG8 | Why it matters |
|---|---|---|---|
| Function | Switched-capacitor voltage inverter (charge pump) | Voltage monitor / supervisory circuit | These devices perform fundamentally different functions, so they are not functionally substitutable in most designs. |
| Output Type | Negative voltage output (inverting charge pump) | Open-drain reset/monitor output | The output signal type determines how the device interfaces with the rest of the circuit. |
| Input Voltage Range | 1.5 V to 5.5 V | 2.0 V to 5.5 V (monitored supply) | The usable supply range affects compatibility with the system power rail. |
| Output Current Capability | Up to approximately 50 mA | Not applicable (logic output only) | Load-driving capability determines whether the part can power downstream circuitry. |
| Typical Operating Frequency | 12 kHz (internal oscillator) | Not applicable | Switching frequency influences output ripple and required capacitor sizing for the charge pump. |
| External Components Required | Two capacitors (fly and reservoir) | None required for basic monitoring | External component count affects board area, cost, and design complexity. |
| Package | 5-pin SOT-23 | 8-pin SOIC (or similar) | Package footprint and pin count must match the PCB layout for a drop-in replacement. |
| Primary Application | Generating negative bias rails from a positive supply | Supply voltage monitoring and reset generation | Intended application defines the role the part plays in the system and whether substitution is feasible. |
Need help validating a replacement?
Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | MAX828EUK | MAX821LUS/GG8 |
|---|---|---|
| Part Status | Obsolete | Active |
| Function | Ratiometric | - |
| Output Configuration | Negative | - |
| Topology | Charge Pump | - |
| Output Type | Fixed | - |
| Number of Outputs | 1 | - |
| Voltage - Input (Min) | 1.5V | - |
| Voltage - Input (Max) | 5.5V | - |
| Voltage - Output (Min/Fixed) | -Vin, 2Vin | - |
| Current - Output | 25mA | - |
| Frequency - Switching | 12kHz | - |
| Synchronous Rectifier | No | - |
| Operating Temperature | -40°C ~ 85°C (TA) | - |
| Mounting Type | Surface Mount | - |
Frequently asked questions
Are the MAX828EUK and MAX821LUS/GG8 interchangeable in a circuit design?
No. The MAX828EUK is a switched-capacitor voltage inverter in a 5-pin SOT-23 package, while the MAX821LUS/GG8 is a microprocessor supervisory circuit in a 4-pin SOT-143 package. They have different functions, pinouts, and electrical characteristics, so they are not interchangeable.
What is the primary function of the MAX828EUK?
The MAX828EUK is a monolithic, CMOS switched-capacitor voltage inverter that converts a positive input voltage to a corresponding negative output voltage. It typically operates from a +1.5 V to +5.5 V input and provides an inverted output with high efficiency.
What is the primary function of the MAX821LUS/GG8?
The MAX821LUS/GG8 is a microprocessor supervisory circuit that monitors the power supply and generates a reset signal for microprocessor systems. It asserts a reset output when the supply voltage falls below a preset threshold, ensuring proper system initialization.
What are the key electrical differences between the MAX828EUK and MAX821LUS/GG8?
The MAX828EUK is a voltage inverter with an output current capability typically up to 20 mA and a switching frequency around 12 kHz. The MAX821LUS/GG8 is a voltage supervisor with a fixed reset threshold (typically 4.63 V for the L version) and a reset timeout period, but it does not invert voltage or source significant load current.
Can the MAX828EUK and MAX821LUS/GG8 operate from the same supply voltage?
The MAX828EUK operates from a supply range of +1.5 V to +5.5 V. The MAX821LUS/GG8 is designed for 5 V systems and monitors a 4.63 V threshold. While both can operate from a 5 V supply, their supply requirements and functions differ, so they are not direct substitutes.
Do the MAX828EUK and MAX821LUS/GG8 have the same package and pinout?
No. The MAX828EUK is offered in a 5-pin SOT-23 package, while the MAX821LUS/GG8 is in a 4-pin SOT-143 package. The pin counts and functions are different, so PCB footprints and connections are not compatible.
Are there any application areas where both the MAX828EUK and MAX821LUS/GG8 could be used together?
Yes. In a system requiring both a negative supply rail and reliable microprocessor reset, the MAX828EUK can generate a negative voltage (e.g., for analog circuitry), while the MAX821LUS/GG8 can supervise the positive supply and reset the processor. They serve complementary roles and can coexist in the same design.