LM66100DCKT - 1.5A Ideal Diode OR Controller 1.5-5.5V SC-70-6 | TI
MPN: LM66100DCKT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.32 | $1.32 |
| 10 | $1.18 | $11.80 |
| 100 | $0.93 | $93.00 |
| 500 | $0.78 | $390.00 |
| 1,000 | $0.66 | $660.00 |
LM66100DCKT Overview
An ideal diode (sometimes called an ORing controller) is a solid-state circuit that emulates a Schottky rectifier using a P-channel MOSFET driven by a small-signal comparator. In conventional power-ORing, two supplies share a load, and the higher-voltage rail takes over; an ideal diode replaces lossy Schottky diodes with active FET control to cut forward-conduction losses to the I²R of the MOSFET instead of the 0.3-0.5 V Schottky drop. This places ideal diodes in the broader hierarchy of discrete semiconductors > diodes > active/ideal diodes > power-ORing devices.
Key electrical features include a sub-30 mV forward regulation setpoint that keeps the device nearly fully on at small sense voltages, true reverse-current blocking when VIN drops below VOUT, an integrated -6 V reverse-polarity protection block eliminating the need for an external TVS clamp, and a logic-level CE pin for on-demand shutdown. The 0.5 UArms quiescent current minimizes battery drain during storage or sleep states, and the open-drain ST pin signals the host when the input is in regulation. The SC-70-6 footprint occupies only 2.0 mm × 1.8 mm of board space, making the part ideal for space-constrained wearables and IoT endpoints.
The internal architecture combines a precision VDS-sensing comparator, a charge-pump gate driver for the P-FET, and a status-flag generator. By sensing drain-to-source voltage directly, the controller avoids the BOM cost and leakage of an external current-sense amplifier, and the internal charge pump guarantees full enhancement of the P-channel FET even at VIN approaching 1.5 V.
Typical applications include power MUXing between USB and a single-cell Li-ion battery in handheld electronics, ORing redundant supplies in PLC and industrial sensor nodes, reverse-polarity protection for field-wired DC inputs, low-dropout switching in energy-harvesting nodes, and load-sharing between a wall adapter and a backup battery in security panels.
When designing with the LM66100DCKT, place the device as close to the input connector as possible so the integrated -6 V reverse block protects downstream rails. The CE pin must be driven high for normal operation; tie it to VIN through a 100 kΩ resistor if shutdown is not used. Add a 1 UArms ceramic bypass capacitor at VIN to suppress transient reverse-current spikes during input hot-plug events.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found on the manufacturer datasheet alone, giving engineers a single decision-ready reference for selecting the LM66100DCKT in next-generation low-power designs.
Drop-in alternatives for LM66100DCKT — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
LM66100DCKR
✅ Drop-In📋 Reference alternative (not in catalog)
LM66100QDCKRQ1
✅ Drop-In📋 Reference alternative (not in catalog)
LM66100DCKR
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
LM66100DCKT Maximum Ratings & Electrical Characteristics
| Product Type | Ideal Diode / OR Controller |
| Topology | Single-Input, Single-Output (SISO) integrated ideal diode |
| Input Voltage Range | 1.5 V to 5.5 V |
| Maximum Continuous Current | 1.5 A |
| On-Resistance (Typical) | 79 mΩ |
| Quiescent Current (IQ) | 0.5 uArms |
| Reverse Voltage Standoff (Polarity Protection) | -6 V |
| Chip Enable (CE) Pin | Yes (active-high logic input) |
| Status (ST) Pin | Open-drain output flag |
| Operating Temperature Range | -40C to +125C |
| Package | SC-70-6 (DCK) |
| Package Size | 2.0 mm x 1.8 mm |
| Thermal Resistance, Theta-JA | 192 C/W |
| Mounting Type | Surface Mount |
| MSL Level | 1 |
| RoHS Status | Compliant |
LM66100DCKT Pin Configuration
| Pin 1 | IN — Input voltage supply (1.5 V to 5.5 V) |
| Pin 2 | GND — Ground reference |
| Pin 3 | CE — Chip enable (active-high logic input) |
| Pin 4 | ST — Status flag (open-drain output) |
| Pin 5 | NC — No internal connection (per datasheet) |
| Pin 6 | OUT — Regulated output to load |
Typical Applications
LM66100DCKT is suitable for 6 applications: USB-C and Battery Power MUXing, Redundant Power Supply ORing in Industrial Sensors, Reverse-Polarity Protection for Field-Wired DC Inputs, Energy-Harvesting Power Path Switching, Wall-Adapter / Battery Load Sharing, Battery Hot-Swap in Portable Medical Devices.
USB-C and Battery Power MUXing
The LM66100DCKT is well suited to ORing a 5 V USB-C VBUS rail against a single-cell Li-ion battery in handheld and wearable devices. Its 1.5-5.5 V input window covers both rails, 79 mΩ on-resistance limits conduction loss to about 0.12 W at 1.5 A, and the 0.5 uArms quiescent current is negligible against USB suspend budgets. The integrated -6 V reverse-polarity block also eliminates the external TVS clamp needed for hot-plug safety, saving roughly 15 mm² of board area. Place two LM66100DCKT devices in a source-select topology with the CE pin driven by the host MCU for priority control; the open-drain ST flag lets the host detect which source is active without an additional ADC channel.
Recommended
Redundant Power Supply ORing in Industrial Sensors
Industrial 4-20 mA loop powered sensors and PLC digital inputs often require seamless switchover between a primary 24 V rail and a backup battery. The LM66100DCKT's 1.5 A continuous rating supports typical sensor loads up to 1.5 A with the 79 mΩ FET dissipating less than 0.2 W at full load. Its sub-30 mV forward regulation setpoint keeps the device nearly fully on during normal operation, so the backup branch stays disconnected until the primary rail fails, preventing reverse-current backfeed. The chip-enable (CE) pin can be wired to a supervisory MCU to force-switchover during maintenance; this enables deterministic redundancy behavior required in process-control installations.
Recommended
Reverse-Polarity Protection for Field-Wired DC Inputs
Factory-floor equipment is routinely mis-wired with reversed DC polarity, which destroys unprotected downstream regulators. The LM66100DCKT integrates -6 V reverse-standoff blocking, eliminating the discrete P-FET + zener string typically used at the input connector. With 79 mΩ on-resistance and 1.5 A rating, the part drops only about 120 mV at full load - far less than a Schottky diode's 300-450 mV forward drop. The CE pin can be tied directly to VIN through a 100 kΩ resistor for always-on protection, or driven low during maintenance to power down the field node safely.
Recommended
Energy-Harvesting Power Path Switching
Solar and thermal energy-harvesting nodes must seamlessly switch between an intermittent harvester and a backup supercapacitor, while wasting as little energy as possible. The LM66100DCKT draws only 0.5 uArms quiescent current, so its own consumption is below the leakage of most harvesters, and its 79 mΩ FET cuts conduction loss to roughly 80 mV at 1 A. The device accepts inputs down to 1.5 V, which covers single-cell photovoltaic outputs as well as supercapacitor stacks discharged to 1.5 V. The open-drain ST pin allows the host MCU to detect when the harvester is contributing and adjust sampling rates to extend service life.
Recommended
Wall-Adapter / Battery Load Sharing
Security panels, e-locks, and access-control devices combine a 5 V wall-adapter supply with a backup battery for fail-safe operation. The LM66100DCKT provides lossless ORing between the adapter and the battery, with the adapter taking priority because its 5 V rail is higher than the battery's 3.0-4.2 V discharge range. When the adapter is unplugged, the LM66100 reverse-blocks within microseconds so the battery does not backfeed the unpowered adapter; this eliminates the diode-OR cross-conduction problem of legacy designs. The 1.5 A continuous rating covers typical access-control loads including RFID readers, solenoid locks, and wireless radios.
Recommended
Battery Hot-Swap in Portable Medical Devices
Handheld diagnostic devices and patient monitors must allow battery replacement without shutting the device off. Two LM66100DCKT devices wired back-to-back at each battery contact isolate the cell during insertion while the device draws power from a holdup capacitor; once the cell is seated, the LM66100 forward-regulates within microseconds and resumes normal supply. The 0.5 uArms quiescent current preserves battery shelf life, and the SC-70-6 footprint leaves room for a smaller battery. The CE pin can be driven by the host MCU to coordinate graceful shutdown before cell removal, and the -6 V reverse block protects against mis-oriented replacements.
Recommended
Recommended Products Summary
Engineering reference data for LM66100DCKT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | LM66100DCKR | LM66100QDCKRQ1 |
|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | SC-70-6 (DCK) | SC-70-6 (DCK) - same | SC-70-6 (DCK) - same |
| Input Voltage Range | 1.5 V to 5.5 V | 1.5 V to 5.5 V | 1.5 V to 5.5 V |
| Continuous Current | 1.5 A | 1.5 A | 1.5 A |
| On-Resistance (Typ) | 79 mΩ | 79 mΩ | 79 mΩ |
| Quiescent Current | 0.5 uArms | 0.5 uArms | 0.5 uArms |
| Reverse-Polarity Standoff | -6 V | -6 V | -6 V |
| Automotive Grade (AEC-Q100) | No | No | Yes (AEC-Q100 qualified) |
| Reel Quantity | 250 pieces (T) | 3000 pieces (R) | 3000 pieces (R) |
Key Differentiators
- Smallest-package 1.5 A ideal diode with reverse-polarity protection (vs LM66100DCKR)
- Drop-in automotive-grade path (vs LM66100QDCKRQ1)
- Integrated -6 V reverse-polarity block saves external TVS (vs Discrete P-FET + zener reverse-polarity circuits)
Design Notes
Place the LM66100DCKT as close as practical to the input connector or battery contact so the integrated -6 V reverse-polarity block protects all downstream traces. Use short, wide VIN and VOUT copper pours to handle 1.5 A continuous current; 1 oz copper with a 20-mil trace drops roughly 30 mV per inch at 1 A. Add a 1 uArms X7R ceramic bypass capacitor directly across VIN and GND within 2 mm of the device to suppress transient reverse-current spikes during hot-plug events.
The SC-70-6 package has a thermal resistance of 192 C/W, so at 1.5 A with VIN=5 V and VOUT=3.3 V the device drops 1.7 V and dissipates about 2.55 W, pushing junction temperature roughly 490 C above ambient - far beyond safe limits. In ORing service this is rarely a problem because forward drop stays under 30 mV (under 50 mW dissipation at 1.5 A), but during hard short or in-rush events the host should fold back load current. Always compute estimated junction rise as delta_T = I^2 * R_DS(on) * theta_JA before committing to layout.
Do not leave the CE pin floating - it must be tied high to VIN through a 100 kΩ resistor, or driven by a logic-level GPIO, for normal operation. Floating CE can cause the part to intermittently disable under noisy input conditions. The ST pin is open-drain and requires an external pull-up resistor (10 kΩ to 100 kΩ typical); leaving it unconnected does not harm the device but loses the input-good indication. Verify pin 5 (NC) is not tied to a noisy trace, as the SC-70-6 pad can couple switching noise into adjacent pins.
Compliance Information
RoHS and REACH compliant per TI product page. Standard LM66100DCKT is NOT AEC-Q100 qualified - select LM66100QDCKRQ1 for automotive applications.
