Part A
ADC0804LCN
Renesas ÉLECTRONIQUE
- Lifecycle
- Active
- Stock
- 1808 PCS
- Series
- Acquisition de données - Convertisseur analogique - numérique (ADC)
Replacement verdict
Compatible functional replacement candidate
The ADC0804LCN and ADC0802LCN share the same 8-bit successive-approximation architecture, 20-pin DIP package, and single 5 V supply, making the ADC0802LCN a viable functional substitute for the ADC0804LCN in most designs. The primary distinction is the absence of an on-chip clock generator on the ADC0802LCN, which requires an external clock source; designers must confirm clock provisioning and verify the differential input configuration before committing to the swap.
Resolution and Architecture
High match
Package Type
High match
Clock Source
Validation required
Analog Input Configuration
Validation required
Parts at a glance
Part B
ADC0802LCN
Société Harris
- Lifecycle
- Active
- Stock
- 5096 PCS
- Series
- Acquisition de données - Convertisseur analogique - numérique (ADC)
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | ADC0804LCN | ADC0802LCN | Why it matters |
|---|---|---|---|
| Resolution | 8 bits | 8 bits | Both converters provide the same 8-bit resolution, so quantization step size and accuracy class are equivalent for substitution. |
| Architecture | Successive approximation | Successive approximation | Identical SAR architecture means similar conversion timing behavior and external interface requirements. |
| Number of analog input channels | 1 (single-ended) | 1 (single-ended) | Both accept a single analog input, so system signal routing and channel count remain unchanged. |
| Supply voltage | 5 V | 5 V | Same 5 V supply requirement allows direct replacement without power rail redesign. |
| Interface type | Parallel (microprocessor-compatible) | Parallel (microprocessor-compatible) | Both use a parallel bus interface, so the host MCU/CPU connection scheme is compatible. |
| On-chip clock circuit | Yes (internal clock generator, external R/C) | No (requires external clock) | The ADC0804 can self-generate its clock with an external resistor/capacitor, while the ADC0802 needs an external clock source, affecting board design and BOM. |
| Conversion time | ~100 µs (with internal clock) | ~100 µs (depends on external clock) | Conversion speed is comparable but the ADC0802's timing depends on the externally supplied clock, which must be designed accordingly. |
| Package | 20-pin DIP | 20-pin DIP | Same package and pin count allow physical drop-in compatibility on the PCB footprint. |
| Operating temperature range | 0 °C to +70 °C (commercial) | 0 °C to +70 °C (commercial) | Identical temperature ratings mean the same environmental operating envelope applies. |
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 | ADC0804LCN | ADC0802LCN |
|---|---|---|
| Supplier | - | Rochester Electronics, LLC |
| Part Status | Obsolete | Active |
| Base Product Number | ADC0804 | - |
| Number of Bits | 8 | - |
| Sampling Rate (Per Second) | 10k | - |
| Number of Inputs | 1 | - |
| Input Type | Differential | - |
| Data Interface | Parallel | - |
| Configuration | ADC | - |
| Number of A / D Converters | 1 | - |
| Architecture | SAR | - |
| Reference Type | External, Supply | - |
| Voltage - Supply, Analog | 4.5V ~ 6.3V | - |
| Voltage - Supply, Digital | 4.5V ~ 6.3V | - |
| Operating Temperature | 0°C ~ 70°C | - |
| Mounting Type | Through Hole | - |
| Packaging | Tube | - |
Frequently asked questions
What is the primary difference between the ADC0804LCN and ADC0802LCN?
The ADC0804LCN and ADC0802LCN are both 8-bit successive-approximation A/D converters from Texas Instruments (originally National Semiconductor) in a 20-pin DIP package. The principal difference is that the ADC0804LCN includes an on-chip clock generator (requiring only an external resistor and capacitor), while the ADC0802LCN requires an external clock signal to be supplied to its CLK IN pin.
Are the ADC0804LCN and ADC0802LCN pin-compatible?
Yes, both devices are offered in the same 20-pin DIP (N) package with the same pinout. However, because the ADC0804LCN can self-clock via its CLK R and CLK IN pins with an external RC network, while the ADC0802LCN requires an external clock at CLK IN, the surrounding clock circuitry differs even though the package footprint is identical.
What is the resolution and conversion architecture of these devices?
Both the ADC0804LCN and ADC0802LCN are 8-bit successive-approximation register (SAR) analog-to-digital converters, providing 8-bit resolution with a differential analog input configuration (VIN+ and VIN−).
What supply voltage do the ADC0804LCN and ADC0802LCN require?
Both devices operate from a single 5 V supply (VCC), which is the standard operating condition specified in the manufacturer datasheet for the ADC0804/ADC0802 family.
How is the clock provided for each device?
The ADC0804LCN has an internal clock generator and only needs an external resistor (between CLK R and CLK IN) and a capacitor (from CLK IN to ground) to set the clock frequency. The ADC0802LCN does not include this internal clock generator and must be driven by an external clock source applied to the CLK IN pin.
Can the ADC0804LCN be used as a drop-in replacement for the ADC0802LCN?
Because the pinout and package are the same, the ADC0804LCN can generally replace the ADC0802LCN, but the board must accommodate the RC clock components on CLK R and CLK IN, and the external clock source used for the ADC0802LCN should be removed or disconnected. The replacement should be validated against the manufacturer datasheet for the specific design.
What is the analog input configuration of these converters?
Both the ADC0804LCN and ADC0802LCN feature differential analog inputs (VIN+ and VIN−), allowing the converter to measure the voltage difference between the two input pins rather than a single-ended input referenced to ground.
Do both devices provide a reference voltage input?
Yes, both the ADC0804LCN and ADC0802LCN provide a VREF/2 pin that sets the analog input voltage span. With VREF/2 left open, the input range is 0 V to 5 V; applying an external reference to VREF/2 adjusts the full-scale input span accordingly, per the manufacturer datasheet.