LMP8646EB - Precision Current Limiter Evaluation Board | Texas Instruments
Référence : LMP8646EB ✓ Actif| Qté | Prix unitaire | Total |
|---|---|---|
| 1 | $205.27 | $205,27 |
| 5 | $195 | $975,00 |
| 10 | $185 | $1 850,00 |
| 25 | $175 | $4 375,00 |
| 50 | $165 | $8 250,00 |
LMP8646EB Présentation
A precision current limiter is a closed-loop analog IC that monitors the voltage across a sense resistor in series with a load and dynamically adjusts the feedback path of an upstream regulator to clamp load current at a programmable threshold. Within the power-management IC hierarchy, current limiters sit between simple fuses/PTVs (one-shot) and complex hot-swap controllers, offering fast (<1 us response), repeatable, resettable protection ideal for hot-swap, USB, PoE, and industrial load circuits.
Key features of the LMP8646 silicon include a wide -2 V to +76 V common-mode input range, configurable gain (5 fixed internal settings: 1, 10, 20, 50, 100) and adjustable bandwidth via the BWL pin, and an open-drain FLAG output that asserts when the current-limit threshold is reached. The EB showcases all of these features through onboard test points, jumpers, and a default 100 mA limit set by RSENSE.
Typical applications include hot-swap protection in -48 V telecom and 24 V industrial rails, precision current source/sink circuits, battery charging current limiting, and high-side current sensing in PLC and motor-drive systems. The combination of high common-mode range and millivolt-level offset makes the LMP8646 a popular reference for 4-20 mA loop protection.
When designing with this evaluation board, engineers should verify that RSENSE power dissipation (I^2 x R) is within rated limits and that upstream regulator loop compensation remains stable under current-limit foldback. Refer to the LMP8646 datasheet for gain-selection trade-offs and the EB user's guide (SNVA594) for jumper-default configurations.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet, enabling faster evaluation and design-in decisions for engineers working on precision current-limiting applications.
Alternatives de remplacement direct pour LMP8646EB — même boîtier, compatible broche à broche. Les références à boîtier différent nécessitant une retouche du PCB sont exclues.
Outil de comparaison rapide — sélectionnez des références alternatives pour une comparaison côte à côte :
Aucune alternative de remplacement direct disponible pour ce produit.
Demander des alternativesLMP8646EB Spécifications
| Product Type | Evaluation Board for Precision Current Limiter |
| Target IC | LMP8646 |
| Target IC Package | SOT-23-6 (DBV) |
| Common-Mode Input Voltage | -2 V to +76 V |
| Configurable Gain Settings | 1, 10, 20, 50, 100 |
| Adjustable Bandwidth Pin | Yes (BWL pin) |
| FLAG Output | Open-drain, asserts at current-limit threshold |
| Sense Resistor | External (RSENSE, user-selectable) |
| Companion Regulator On-board | LM3102 Step-Down Switching Regulator, 2.5 A |
| Operating Temperature (IC) | -40C to +125C |
| Statut RoHS | Compliant (per NOPB suffix) |
| Lead-Free | Yes (NOPB suffix) |
Guide de configuration des broches du LMP8646EB sot-23-6 (dbv)
Configuration des broches du LMP8646EB (boîtier sot-23-6 (dbv)). La numérotation des broches, les fonctions et les schémas de connexion sont définis dans la fiche technique du fabricant. Consultez-la pour l'empreinte exacte et les directives de soudage.
Aucune donnée de brochage détaillée disponible pour LMP8646EB.
Consultez la fiche technique pour la configuration complète des broches.
Applications typiques
LMP8646EB convient pour 7 applications: 24V Industrial Hot-Swap Protection, Telecom -48V Rail Current Limiting, USB and PoE Port Current Limiting, Precision Battery Charger Current Regulation, High-Side Motor Current Sensing, Solar PV String Current Monitoring, 4-20 mA Industrial Loop Protection.
24V Industrial Hot-Swap Protection
The LMP8646EB's 76 V common-mode range and microsecond response time make it ideal for hot-swap protection in 24 V industrial PLC, motor-driver, and factory-automation rails. According to the TI datasheet, the LMP8646 monitors the sense resistor placed in series with the load and dynamically reduces upstream regulator feedback to clamp inrush current during card insertion, preventing connector arcing and backplane collapse. Unlike a fuse, the LMP8646 resets automatically once the fault clears, and its open-drain FLAG output can interrupt the system controller for diagnostic logging.
Recommandé
Telecom -48V Rail Current Limiting
The LMP8646EB's -2 V to +76 V common-mode range covers the full -48 V telecom bus envelope, including transients during load steps. According to TI's LMP8646 datasheet, the device's high-side sensing eliminates ground-shift errors in distributed -48 V systems, and its configurable gain (1x to 100x) supports loads from milliamps to several amps with a single IC. The on-board LM3102 regulator demonstrates a complete isolated-bus-derived current-limited supply, useful for powering line-interface cards from a central -48 V backplane.
Recommandé
USB and PoE Port Current Limiting
The LMP8646EB provides a USB-compliant current-limit reference design, where the LMP8646 clamps load current at 500 mA (USB 2.0) or 900 mA (USB 3.0) by adjusting the upstream regulator feedback. According to TI application literature, the LMP8646's fast foldback protects USB controllers from short-circuit and over-current events within the 100 us USB spec window. PoE applications benefit similarly, with the FLAG output driving an optocoupler or power-MOSFET gate for sub-millisecond fault isolation.
Recommandé
Precision Battery Charger Current Regulation
The LMP8646EB is well suited for Li-ion and lead-acid battery charging applications where constant-current regulation is critical during the bulk-charge phase. According to the TI datasheet, the LMP8646 monitors the high-side current via an external sense resistor and continuously adjusts the regulator to maintain a programmable I_CHRG threshold, eliminating the need for a dedicated charger IC in cost-sensitive designs. The -40C to +125C operating range supports outdoor and automotive battery-pack environments.
Recommandé
High-Side Motor Current Sensing
The LMP8646EB enables accurate high-side current sensing in brushed-DC and stepper motor drives, where ground-referenced current shunts would inject switching noise into the logic ground. According to TI application notes, the LMP8646's wide common-mode range accommodates the motor supply rail (12 V to 48 V typical) plus inductive kickback transients, while the configurable bandwidth (via the BWL pin) lets designers trade off noise vs step-response for PWM-frequency operation up to several hundred kilohertz.
Recommandé
Solar PV String Current Monitoring
The LMP8646EB's 76 V common-mode range is suitable for monitoring individual panel currents in 24 V solar PV strings, where the sense resistor drops only millivolts in the high-current return path. According to TI's LMP8646 datasheet, the device's low offset and high gain enable accurate measurement of panel currents from sub-amp to tens of amps without disrupting ground-referenced MPPT controllers. The on-board LM3102 regulator demonstrates an isolated DC-DC supply for the monitor circuit.
Recommandé
4-20 mA Industrial Loop Protection
The LMP8646EB demonstrates precision current limiting for 4-20 mA industrial analog loops, where the LMP8646 clamps loop current at 25-30 mA to protect downstream sensors and DACs from field-wiring faults. According to TI datasheet information, the LMP8646's 76 V common-mode range handles loop supply transients, and its high gain (100x) allows use of very small sense resistors to maintain loop compliance voltage headroom. The on-board LM3102 shows a complete loop-powered current source.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour LMP8646EB — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | LMP8646EB/NOPB | LMP8645MDBV | LMP8646MDBV | INA300AIDBVR | MAX4211AETE |
|---|---|---|---|---|---|---|
| Package | Evaluation Board (SOT-23-6 IC) | Evaluation Board (SOT-23-6 IC) | SOT-23-6 (IC only) | SOT-23-6 (IC only) | SOT-23-6 (IC only) | TDFN-16 |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Maxim Integrated |
| Common-Mode Range | -2 V to +76 V | -2 V to +76 V | -2 V to +76 V | -2 V to +76 V | 0 V to +36 V | -0.3 V to +30 V |
| Function | Precision Current Limiter | Precision Current Limiter | Precision Current Limiter (no BWL) | Precision Current Limiter | Overcurrent Comparator | Current-Sense Amplifier |
| Adjustable Bandwidth Pin | Yes (BWL pin) | Yes | No | Yes | No | No |
| Output Stage | FB-adjust to upstream regulator | FB-adjust | FB-adjust | FB-adjust | Open-drain ALERT | Analog voltage output |
| Closed-Loop Regulation | Yes (analog foldback) | Yes | Yes | Yes | No (alert only) | No (monitor only) |
Principaux différenciateurs
- True closed-loop current regulation with analog foldback (vs INA300AIDBVR)
- Wider 76 V common-mode range vs 36 V typical (vs INA300AIDBVR)
- Adjustable bandwidth (BWL pin) for noise vs speed trade-off (vs LMP8645MDBV)
Notes de conception
Estimated: The LMP8646 in SOT-23-6 has a theta_JA of approximately 200 C/W (typical for the package). At maximum continuous sense-resistor dissipation (e.g., 100 mA limit with 1 ohm sense = 10 mW), self-heating is negligible. However, if the application uses a high-current sense resistor in the same thermal path (e.g., 0.01 ohm at 5 A = 250 mW), size the resistor with adequate copper land area to limit hotspot temperature rise above the LMP8646's 125C junction limit.
Route the LMP8646's sense-resistor traces as a differential pair (Kelvin connection) directly to the sense resistor pads, avoiding via stubs and ground loops. Place the bypass capacitor (typically 100 nF X7R) as close as possible to the LMP8646's supply pin. For the EB layout, follow TI's recommended 4-layer stack-up to minimize noise coupling from the LM3102 switching regulator node into the high-impedance sense inputs.
Do not exceed the LMP8646's absolute maximum common-mode voltage of 76 V - inductive kickback from motor or relay loads can easily exceed this on a 24 V or 48 V rail. Add a TVS diode or transient suppressor across the sense resistor for hot-plug applications. Also, ensure the GAIN pin is not left floating; it must be tied high or low to one of the five valid gain settings, or the output behavior is undefined per the TI datasheet.
For high-side sensing, the LMP8646's supply pin (VDD) must be biased relative to the load-side common-mode voltage, typically via a high-voltage Zener or resistor-divider-fed LDO. On the EB, the LM3102 switching regulator provides this bias. For low-side sensing, the VDD pin can be tied to a fixed 5 V or 3.3 V logic rail. Decouple the VDD pin with at least 100 nF of low-ESR ceramic and consider a bulk capacitor for noisy environments.
Informations de conformité
LMP8646EB/NOPB suffix confirms lead-free, RoHS-compliant construction per TI part-numbering convention. Base LMP8646EB (without NOPB) may not be RoHS compliant; always order the /NOPB variant for new designs. AEC-Q100 qualification not applicable for evaluation boards; the underlying LMP8646 IC does not carry automotive qualification per verified web data.
