LM2903ITLX/NOPB - Dual Low-Power Open-Collector Comparator, 8-DSBGA
Référence : LM2903ITLX/NOPB ✓ ActifLM2903ITLX/NOPB Présentation
A comparator is a differential input amplifier whose output switches state when one input exceeds the other by more than the offset voltage. Comparators sit at the bottom of the analog signal chain as the decision element that converts a small analog difference into a logic-level event. The LM2903 belongs to the LM193/LM2903/LM393 family, a classic general-purpose voltage comparator family, and this device adds a low-power, wide-supply differential pair plus a saturating open-collector transistor output stage.
Key features of the LM2903ITLX/NOPB include open-collector outputs that can be pulled up to any logic level up to the supply rail, differential input range of plus or minus 18 V, common-mode input voltage range that includes ground, an industrial temperature grade of -40 C to +85 C, and total quiescent current of 2.5 mA maximum for the pair. The open-collector architecture allows multiple comparators to be wire-ORed on a shared pull-up resistor, which is the standard technique for driving slow, high-voltage relay, lamp, or open-drain bus loads.
Internally the device is a bipolar dual-diff-pair design with an emitter-stabilized differential input stage feeding a saturated open-collector output transistor. Because the output stage is open collector rather than push-pull, output rise and fall times are set by the pull-up resistor and the load capacitance rather than by an internal driver, which allows a designer to trade speed for EMI margin. The wide 2 V to 36 V supply span lets a single part sense signals referenced to either a low-voltage logic rail or a 24 V industrial bus.
Typical applications include over/under-voltage and window monitoring in power supplies, sensor threshold conditioning for industrial and automotive sensing chains, zero-cross and level detection in motor control and drive electronics, open-drain bus arbitration in multi-drop industrial networks, and general-purpose analog signal conditioning where an open-collector output must drive a relay or an opto-isolator.
Design consideration: because the outputs are open collector, an external pull-up resistor is mandatory, and its value sets the output rise time. Keep pull-ups high enough to limit sink current within the 16 mA typical output rating, and low enough to achieve the required switching speed with the total bus capacitance.
This page consolidates parametric detail, drop-in alternatives for the same 8-DSBGA footprint, and practical layout and pull-up guidance that is not assembled in one place in the original LM2903 documentation.
Alternatives de remplacement direct pour LM2903ITLX/NOPB — 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 LM2903ITLX/NOPB (même facteur de forme et même empreinte) — différant par Comparator Type, Input Bias Current, Input Offset Voltage, Number of Channels, Package.
LM2903ITL/NOPB
✅ Remplacement directContactez-nous pour le prix
Voir la fiche technique →LM2903ITLX
✅ Remplacement direct📋 Alternative de référence (hors catalogue)
LM2903-N
✅ Remplacement direct ⚠️ Spécifications non vérifiées📋 Alternative de référence (hors catalogue)
LM2903BIDR
✅ Remplacement direct ⚠️ Spécifications non vérifiéesContactez-nous pour le prix
Voir la fiche technique →LM2903ITLX/NOPB Valeurs maximales et caractéristiques électriques
| Comparator Type | Differential, general purpose |
| Number of Channels | 2 |
| Supply Voltage Range | 2 V to 36 V |
| Dual Supply Operation | +/-1 V to +/-18 V |
| Input Offset Voltage | 2.0 mV max (LM193 series) |
| Input Bias Current | 0.25 uA max at 5 V |
| Output Current (Typ) | 16 mA at 5 V |
| Courant de repos | 2.5 mA max |
| Propagation Delay | 700 ns max |
| Type de sortie | Open-Collector |
| Compatible Output Levels | CMOS, DTL, ECL, MOS, TTL |
| Température de fonctionnement | -40 C to +85 C |
| Boîtier | 8-DSBGA (8-WFBGA), 2 x 2 mm |
| Terminal Form | Ball |
| Type de montage | Surface Mount |
| Number of Terminals | 8 |
Configuration des broches de LM2903ITLX/NOPB
| Broche 1 | OUT1 — Comparator 1 open-collector output |
| Broche 2 | IN1- — Comparator 1 inverting input |
| Broche 3 | IN1+ — Comparator 1 non-inverting input |
| Broche 4 | V- — Negative supply or ground |
| Broche 5 | IN2+ — Comparator 2 non-inverting input |
| Broche 6 | IN2- — Comparator 2 inverting input |
| Broche 7 | OUT2 — Comparator 2 open-collector output |
| Broche 8 | V+ — Positive supply |
Applications typiques
LM2903ITLX/NOPB convient pour 6 applications: Power Supply Over/Under-Voltage Monitoring, Industrial Sensor Threshold Conditioning, Open-Drain Bus Arbitration and Level Detection, Motor Drive and Zero-Cross Detection, Automotive and Off-Highway Level Detection, Portable and Battery-Powered Monitoring.
Power Supply Over/Under-Voltage Monitoring
The LM2903ITLX/NOPB is well suited to window supervision in industrial and telecom power supplies because its 2 V to 36 V supply span tracks the rectified bus directly, while the differential inputs accept plus or minus 18 V around a mid-supply reference. Two independent channels let one part implement both an over-voltage and an under-voltage trip point without adding a second IC. The 2.0 mV maximum input offset of the LM193 series keeps the trip points accurate at low supply levels, and the open-collector outputs can pull down a system fault line or an opto-isolator LED through a pull-up resistor, giving a fail-safe hardware shutdown path that does not depend on firmware polling. Because the outputs are open collector, the fault line can be wire-ORed with other supervisors and works with any logic level by choosing the pull-up rail.
Recommandé
Industrial Sensor Threshold Conditioning
Conditioning raw transducer outputs into logic decisions is the classic comparator job, and the LM2903ITLX/NOPB fits here with its low 0.25 uA maximum input bias current at 5 V, which limits the error introduced when the sensor source impedance is high. The 2.0 mV maximum offset voltage in the LM193 series allows a narrow hysteresis band around the threshold, so small process or temperature shifts do not cause chatter at the output. Place each channel across the sensor bridge output and a precision reference, pull the open-collector output up to the local logic rail, and the device produces a clean digital transition for the downstream microcontroller. The wide supply range also lets the comparator operate directly from a 24 V loop-powered transmitter's unregulated rail.
Recommandé
Open-Drain Bus Arbitration and Level Detection
The open-collector output of the LM2903ITLX/NOPB makes it a natural fit for wired-OR bus arbitration, where any one of several devices can pull the shared line low. Its 700 ns maximum propagation delay is fast enough for moderate-rate handshake and presence-detect protocols, and the differential inputs allow detection of the bus state referenced to a mid-supply bias rather than to ground. Because the output can sink 16 mA typical at 5 V, the line can drive an opto-isolator input, a relay driver, or a legacy open-collector bus directly. Pull the line up to the maximum-rated voltage of whichever bus segment it belongs to, keeping total capacitance low to preserve rise time.
Recommandé
Motor Drive and Zero-Cross Detection
In motor control and power-conversion electronics, the LM2903ITLX/NOPB can detect zero crossings or commutation edges of a back-EMF or mains-derived signal because its differential inputs tolerate plus or minus 18 V swings referenced to a biased mid-supply node. The comparator converts that crossing into a crisp edge for the gate driver or controller, improving timing accuracy over software-only detection. The open-collector output can sink into a gate-driver enable input or an optocoupler LED, while the wide 2 V to 36 V supply lets the device sit directly on a rectified auxiliary rail. Note that this is an industrial-grade part, so confirm the transient and isolation requirements of the specific motor platform before deploying.
Recommandé
Automotive and Off-Highway Level Detection
The -40 C to +85 C industrial temperature range of the LM2903ITLX/NOPB covers many off-highway, agricultural, and heavy-equipment level-detection tasks where a discrete transistor or generic commercial comparator would drift with temperature. The open-collector output can sink a lamp or relay driver stage, and the wide supply range handles cranking and load-dump conditions on 12 V and 24 V systems. The differential inputs allow the sensing element to be referenced to the chassis or battery negative without common-mode complications. For true automotive-grade production, choose an AEC-Q100-qualified ordering of the family and re-validate the transient immunity, since the DSBGA suffix in this listing is the industrial grade.
Recommandé
Portable and Battery-Powered Monitoring
The low 2.5 mA maximum quiescent current of the LM2903ITLX/NOPB makes it practical in battery-powered equipment where the comparator must sit enabled for long periods while monitoring a battery or fuel-gauge cell. The LM193-family low drain from the differential input stage is a recognized advantage when the device interfaces directly with MOS logic, and it allows the sensing network to sit at high impedance without bias errors. The 8-DSBGA footprint occupies roughly 2 x 2 mm, which matters in wearables, handheld meters, and compact IoT nodes where board area is at a premium. Keep the pull-up resistor high and the leak currents low so that standby current is not dominated by the pull-up path.
Recommandé
Récapitulatif des produits recommandés
Données de référence d'ingénierie pour LM2903ITLX/NOPB — comparaison, recommandations de conception et informations de conformité.
Guide de sélection
Comparaison avec les alternatives
| Paramètre | Ce produit | LM2903ITL/NOPB | LM2903ITLX | LM2903-N | LM2903 |
|---|---|---|---|---|---|
| Package | 8-DSBGA (8-WFBGA), 2 x 2 mm | 8-DSBGA (8-WFBGA) - same | 8-DSBGA (8-WFBGA) - same | 8-DSBGA (8-WFBGA) - same | 8-DSBGA (8-WFBGA) - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Number of Channels | 2 | 2 | 2 | 2 | 2 |
| Supply Voltage Range | 2 V to 36 V | 2 V to 36 V | 2 V to 36 V | 2 V to 36 V | 2 V to 36 V |
| Output Type | Open-Collector | Open-Collector | Open-Collector | Open-Collector | Open-Collector |
| Input Offset Voltage | 2.0 mV max (LM193 series) | 2.0 mV max (LM193 series) | 2.0 mV max (LM193 series) | 2.0 mV max (LM193 series) | 2.0 mV max (LM193 series) |
| Input Bias Current | 0.25 uA max at 5 V | 0.25 uA max at 5 V | 0.25 uA max at 5 V | 0.25 uA max at 5 V | 0.25 uA max at 5 V |
| Propagation Delay | 700 ns max | 700 ns max | 700 ns max | 700 ns max | 700 ns max |
| Quiescent Current | 2.5 mA max | 2.5 mA max | 2.5 mA max | 2.5 mA max | 2.5 mA max |
| Operating Temperature | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | 0 C to +70 C |
| Output Sink Current (Typ) | 16 mA at 5 V | 16 mA at 5 V | 16 mA at 5 V | 16 mA at 5 V | 16 mA at 5 V |
Principaux différenciateurs
- Extremely small footprint for a dual comparator (vs LM2903DR)
- Wide supply tolerance for direct bus-referenced sensing (vs LM393ADR)
- Low offset and low bias for accurate thresholding (vs LM2902DR)
- Open-collector flexibility versus push-pull comparators (vs LM2903-N (same topology))
Notes de conception
An open-collector output does not produce a high level by itself. Every output node in this design must have a pull-up resistor to a positive rail, and omitting it leaves the node floating with unpredictable logic state. Size the resistor so that worst-case sink current stays below the 16 mA typical output rating at 5 V, while keeping it low enough that the RC rise time with total bus capacitance meets the required settling window.
The 8-DSBGA uses 12 mil large bumps on a very fine pitch, so plan escape routing with via fan-out before placing the part. Place the pull-up resistors and any input filtering network close to the balls to keep the open-collector trace short and reduce susceptibility to coupled noise on the high-impedance input nodes. Provide a solid ground plane and a dedicated return path under the device to keep the differential inputs away from switching-node copper.
Because the open-collector output is a saturating bipolar transistor, the falling edge is fast while the rising edge is set by the pull-up resistor and the load capacitance. Estimate: with a 10 kOhm pull-up and 100 pF total load, the 10-90 percent rise time is about 2.2 x R x C, or roughly 2.2 us. Shorter pull-ups speed up the rising edge but raise the static sink current, so pick the value from the required edge rate rather than by default.
The input common-mode range includes ground, so bias both differential inputs within the valid window around the supply rails and avoid letting either input sit at or below the negative rail for long periods, since the base-emitter junction of the input pair can conduct and disturb the offset. For single-supply operation, bias the reference network to mid-supply with a low-impedance divider, and keep the divider current high enough that the 0.25 uA maximum input bias current contributes less than a millivolt of error.
Informations de conformité
The LM2903ITLX/NOPB is an industrial-grade (-40 C to +85 C) dual comparator in an 8-DSBGA package. It is not offered with AEC-Q100 automotive qualification under this ordering code. Confirm RoHS, REACH, lead-free and halogen-free status against the current manufacturer product page and material declaration for the exact suffix before release to production.
