MAX138CPL+ - 3.5-Digit ADC with LCD Drivers | Maxim Integrated
Référence : MAX138CPL+ ✓ ActifMAX138CPL+ Présentation
A display-drive ADC is a specialized data-conversion IC that converts an analog input into a digital value and directly interfaces that value with display drivers. Within the broader hierarchy, the MAX138CPL+ is an ADC, then a display converter, then a data-conversion IC, and finally a power-management and signal-conditioning semiconductor. Its internal charge-pump inverter allows bipolar voltage measurement while the device itself operates from one supply polarity.
The MAX138CPL+ combines a 3.5-digit conversion system, bandgap reference, charge-pump voltage converter, and direct LED drivers in one integrated circuit. A single +2.5V to +7V operating range supports low-voltage portable systems as well as higher-voltage industrial panel meters. The integrated reference and display drivers are particularly useful when component count, board area, and assembly complexity must be minimized.
Its dual-slope conversion architecture and display-oriented feature set target measurements that require readable decimal results rather than high-speed sampled waveforms. The charge-pump inverter enables positive and negative input measurements from a single supply. Direct LED drivers provide the output path for multiplexed or segment-driven displays, reducing the need for separate display-interface circuitry.
Typical applications include digital panel meters, laboratory measurement instruments, industrial process displays, temperature-measurement panels, and portable monitoring equipment. The device is particularly appropriate where a compact front panel must show three-and-a-half decimal digits from a bipolar analog input. Designers must verify input-range, display-segment, and timing requirements against the manufacturer datasheet before finalizing the panel design.
The principal design consideration is preserving the required bipolar input range while keeping the charge pump and reference within their specified operating limits. Input filtering, reference stability, display contrast, and grounding directly affect displayed accuracy. Layout should separate sensitive analog inputs from display-driver return currents and provide suitable bypassing close to the supply pins.
This product page consolidates manufacturer functionality, distributor availability, observed pricing, same-package alternatives, and practical panel-meter design guidance. It also distinguishes documented drop-in variants from merely similar converter families, helping engineers narrow replacement choices without treating unrelated ADC functions as pin-compatible substitutes.
Alternatives de remplacement direct pour MAX138CPL+ — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Variantes de cette série
Modèles de la même série directement compatibles avec MAX138CPL+ (même facteur de forme et même empreinte) — différant par Integrated Reference, Package, Supply Voltage Range.
MAX138CPL
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
MAX138CPL-
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
MAX138EPL+
✅ Remplacement directContactez-nous pour le prix
Voir la fiche technique →MAX138EPL
✅ Remplacement direct ⚠️ Spécifications non vérifiées📋 Alternative de référence (hors catalogue)
MAX138CPL+ Valeurs maximales et caractéristiques électriques
| Converter Type | 3.5-digit dual-slope ADC with direct LED drivers |
| Résolution | 3.5 digits |
| Supply Voltage Range | +2.5V to +7V |
| Input Type | Bipolar input |
| Integrated Reference | Yes, bandgap reference |
| Charge-Pump Inverter | Yes |
| Display Output | Direct LED drivers |
| Boîtier | 40-pin PDIP |
| Package Height | 0.600 inch (15.24 mm) |
| Type de montage | Through-hole |
| Manufacturer List Price | $17.21 starting from, 1ku quantity |
| Observed LCSC Price | $8.6025 starting price |
| Observed Heisener Unit Price | $27.4645 |
| Lifecycle Statement | PRODUCTION |
Guide de configuration des broches du MAX138CPL+ 0.600 inch (15.24 mm)
Configuration des broches du MAX138CPL+ (boîtier 0.600 inch (15.24 mm)). Ce composant analogique comporte des broches d'entrée, de sortie et d'alimentation. Consultez la fiche technique du fabricant pour les configurations des broches d'annulation d'offset, de compensation et d'activation. Idéal pour le conditionnement de signaux et les circuits amplificateurs.
Aucune donnée de brochage détaillée disponible pour MAX138CPL+.
Consultez la fiche technique pour la configuration complète des broches.
Applications typiques
MAX138CPL+ convient pour 6 applications: Digital Panel Meters, Industrial Process Displays, Laboratory Measurement Instruments, Temperature Measurement Panels, Portable Measurement Devices, Embedded Instrumentation Readouts.
Digital Panel Meters
The MAX138CPL+ fits digital panel meters because it combines a 3.5-digit ADC, integrated bandgap reference, charge-pump inverter, and direct LED drivers in one 40-pin PDIP device. Its single +2.5V to +7V supply simplifies instrumentation powered from regulated rails, while the integrated reference reduces external support circuitry. The bipolar-input architecture is useful when the meter must display positive and negative measurements from a single-polarity supply. In a panel-meter implementation, the analog input feeds the converter while the on-chip display drivers address the LED or LCD segments. The main benefit is lower component count and reduced board complexity compared with a separate ADC and display interface. Engineers must still confirm input limits, conversion timing, segment configuration, and display polarity against the manufacturer data sheet.
Recommandé
Industrial Process Displays
The MAX138CPL+ is suitable for compact industrial process displays that require a readable three-and-a-half-digit result and bipolar measurement capability. Its integrated reference, charge-pump inverter, and direct LED drivers reduce the number of external components needed around a front-panel display. Operating from a single +2.5V to +7V supply also simplifies integration with regulated industrial electronics. The device can sit near the analog sensor input and drive the display locally, reducing the number of signals routed across the board. For robust industrial use, engineers should verify the exact suffix temperature grade, input protection requirements, EMC behavior, and whether galvanic isolation is needed upstream of the converter.
Recommandé
Laboratory Measurement Instruments
The MAX138CPL+ can support laboratory instruments that present a bipolar measurement as a three-and-a-half-digit display. The integrated bandgap reference and charge-pump inverter provide the core measurement functions in one package, while direct LED drivers reduce the need for a separate display controller. Its +2.5V to +7V operating range supports both compact portable instruments and higher-voltage bench equipment. In a front-panel design, the converter can operate close to the measurement input while the regulated supply feeds both the analog and display sections. Designers should account for input settling, reference accuracy, display update behavior, and thermal drift rather than assuming generic ADC specifications apply.
Recommandé
Temperature Measurement Panels
The MAX138CPL+ fits temperature-measurement panels where a sensor signal must be converted into a straightforward numeric display. Its 3.5-digit resolution is appropriate for many panel indicators, and the integrated reference and bipolar-input support can simplify measurement conditioning compared with a discrete converter and display interface. A single +2.5V to +7V supply provides flexibility for portable thermometers, HVAC controls, and monitoring instruments. The converter can be placed near the sensor input to keep sensitive analog routing short, while its integrated display drivers connect directly to the visual output. Calibration, sensor excitation, linearity, and the operating-temperature grade must be evaluated in the complete measurement chain rather than inferred from display resolution alone.
Recommandé
Portable Measurement Devices
The MAX138CPL+ supports portable measurement devices because it combines conversion, reference, charge-pump, and display-driving functions while operating from a single +2.5V to +7V supply. That integration can reduce board area and external component count compared with separate measurement and display blocks. The 40-pin PDIP package is appropriate for through-hole laboratory-style products and relatively conservative industrial designs. A portable instrument can use the on-chip display drivers for a direct numerical readout while retaining the same supply rail for the analog front end. Designers should calculate available power budget, verify startup and display settling, and confirm that the selected suffix satisfies the product's ambient-temperature requirements.
Recommandé
Embedded Instrumentation Readouts
The MAX138CPL+ is appropriate for embedded instrumentation readouts that need a local numerical display beside a sensor or measurement circuit. Its integrated direct LED drivers and 3.5-digit conversion system avoid a separate display-interface IC, while the charge-pump inverter enables bipolar measurement from one supply. The +2.5V to +7V operating range allows the readout to share power with compatible embedded electronics. In this architecture, the MAX138CPL+ converts the analog value and updates the panel display locally, leaving the main controller free for control functions. The designer should verify the display technology, segment count, input range, reference layout, and whether the DIP footprint remains practical for the target assembly process.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour MAX138CPL+ — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | MAX138CPL | MAX138CPL- | MAX138EPL+ | MAX138EPL |
|---|---|---|---|---|---|
| Package | 40-pin PDIP | 40-pin PDIP | 40-pin PDIP | 40-pin PDIP | 40-pin PDIP |
| Brand | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated | Maxim Integrated |
| Resolution | 3.5 digits | 3.5 digits | 3.5 digits | 3.5 digits | 3.5 digits |
| Supply Voltage Range | +2.5V to +7V | +2.5V to +7V | +2.5V to +7V | +2.5V to +7V | +2.5V to +7V |
| Input Type | Bipolar | Bipolar | Bipolar | Bipolar | Bipolar |
| Integrated Reference | Yes | Yes | Yes | Yes | Yes |
| Charge-Pump Inverter | Yes | Yes | Yes | Yes | Yes |
| Display Drivers | Direct LED drivers | Direct LED drivers | Direct LED drivers | Direct LED drivers | Direct LED drivers |
Principaux différenciateurs
- Integration reduces separate display-interface circuitry (vs MAX131AEPL+)
- Single-supply bipolar measurement capability (vs MAX138CPL)
- Verified same-footprint family alternatives (vs MAX138EPL+)
Notes de conception
Route the bipolar analog input away from display-driver switching paths and the charge-pump output region. Keep the input connection short, use a quiet ground reference for the analog return, and place input filtering close to the source. Because the device combines analog conversion and display drive on one DIP, cross-coupled display currents can create measurement errors even when the logic supply is properly decoupled.
Decouple the +2.5V to +7V supply locally and follow the manufacturer recommendations for bypass capacitance and charge-pump stability. The verified data confirms the valid supply range but does not specify capacitor values, so do not substitute guessed values for the datasheet requirements. Verify startup behavior and supply ripple at the selected operating voltage because the integrated reference and bipolar inverter can be sensitive to supply disturbance.
Do not treat a generic 3.5-digit ADC as a drop-in substitute. The MAX138CPL+ integrates a reference, charge-pump inverter, and direct LED drivers, so a replacement must match the 40-pin PDIP footprint and display functions. MAX138CPL, MAX138CPL-, MAX138EPL+, and MAX138EPL are the supported same-family candidates identified here; confirm the exact suffix, temperature grade, pinout, and stock before purchasing.
Plan the 40-pin through-hole footprint with adequate spacing for the display assembly and nearby sensor electronics. Keep sensitive analog traces away from display and switched-supply current loops, and use a low-impedance ground plane where practical. The verified web data does not include the complete pin map or recommended layout, so the official manufacturer data sheet must be used for every connection and keep-out requirement.
Informations de conformité
The supplied verified data identifies the device as a Maxim Integrated 40-pin PDIP ADC but does not provide RoHS, REACH, lead-free, halogen-free, or conflict-minerals declarations. AEC-Q100 is not applicable to this catalog classification because the part is not presented as an automotive-qualified product.