My Inquiry
My Account
Analog Devices Inc./Maxim Integrated MAX1973EUB+
- Part No.:
- MAX1973EUB+
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Package:
- 10-TFSOP, 10-MSOP (0.118", 3.00mm Width)
- Datasheet:
-
MAX1973EUB+.pdf
- Description:
- IC REG BUCK ADJ 1A 10UMAX
- Quantity:
- Payment:
- Shipping:
Inventory:2,853
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
The MAX1973EUB+ from Maxim Integrated is a constant-frequency 1.4MHz PWM current-mode step-down DC/DC regulator delivering up to 1A output current with ±1% output voltage accuracy over load, line, and temperature. It supports preset outputs of 1.8V or 2.5V (via FBSEL pin), or adjustable down to 1.25V, and features logic-controlled ±4% voltage margining for production test validation. It is used in DSP/ASIC core supplies and telecom power rails where compact size and fast transient response are critical.
For engineers reviewing the MAX1973EUB+ datasheet, MAX1973EUB+ pinout, MAX1973EUB+ application, or MAX1973EUB+ equivalent, key selection considerations include its 10-pin µMAX package, 2.6V–5.5V input range, 1.4MHz fixed switching frequency outside DSL bands, 100% duty-cycle dropout capability, and integrated synchronous rectification eliminating external Schottky diodes.
Technical Context
The MAX1973EUB+ employs a fixed-frequency current-mode PWM control architecture with internal slope compensation to prevent subharmonic oscillation and ensure stability across wide VIN/VOUT ratios. Its transconductance error amplifier (40–80µS) interfaces with an external RC network on the COMP pin to set loop bandwidth near 140kHz-optimized for fast load transient response while maintaining phase margin.
It integrates high-side P-channel and low-side N-channel MOSFETs with on-resistances of 0.23Ω (high-side typ) and 0.16Ω (low-side typ), enabling synchronous rectification and high efficiency. Current sensing uses MOSFET RDS(ON) without external resistors, and thermal shutdown activates at +170°C with 20°C hysteresis.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 2.6V to 5.5V - supports single-cell Li-ion, 3.3V, and 5V rail inputs without external LDO pre-regulation. |
| Output Current | 1A continuous - sufficient for DSP, ASIC, and FPGA core supplies in telecom and networking equipment. |
| Switching Frequency | 1.4MHz (1.2–1.6MHz) - enables use of small 2.2–4.7µH inductors and 4.7µF ceramic capacitors, reducing board area by >50% vs. 500kHz solutions. |
| Output Voltage Accuracy | ±1% over load, line, and temperature - ensures reliable operation of voltage-sensitive digital loads without post-regulation. |
| Voltage Margining | ±4% via CTL1/CTL2 logic inputs - allows automated high/low supply stress testing during board-level burn-in and functional test. |
| Duty-Cycle Capability | 100% - maintains regulation under ultra-low dropout conditions (e.g., VOUT = 3.3V with VIN = 3.4V), minimizing heat dissipation. |
| Package | 10-pin µMAX (3mm × 3mm × 0.8mm) - surface-mount, thermally enhanced package with exposed PGND pad for efficient heat transfer. |
Pinout & Package
The MAX1973EUB+ is housed in a 10-pin µMAX package with exposed power ground (PGND) pad for thermal performance. Pin 1 is marked with a dot; pin numbering proceeds counterclockwise.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (FBSEL) | Feedback Mode Selector | Logic input selecting preset output: GND → 1.8V, IN → 2.5V, open → adjustable mode (1.25V–VIN). |
| 2 (COMP) | Compensation Node | Connects external RC network to stabilize control loop; internally pulled to GND during shutdown or UVLO. |
| 3 (FB) | Feedback Input | Monitors output voltage directly (preset mode) or via resistor divider (adjustable mode); sets regulation point with ±1% accuracy. |
| 4 (SS) | Soft-Start / Reference Output | Charged by 20µA current source to ramp output voltage; also provides 1.25V reference for external circuitry. |
| 5 (GND) | Analog Ground | Reference node for FB, COMP, and SS; must be tied to PGND at single point to minimize noise coupling. |
| 6 (CTL2) | Control Input 2 | Logic input enabling voltage margining (±4%) or shutdown when paired with CTL1 per truth table. |
| 7 (PGND) | Power Ground | High-current return path for LX switch node and input/output capacitors; connects to exposed thermal pad. |
| 8 (LX) | Switch Node | Drives external inductor; integrates synchronous rectifier - no external freewheeling diode required. |
| 9 (IN) | Input Supply | Accepts 2.6–5.5V; requires 4.7µF ceramic capacitor to PGND for EMI suppression and input ripple reduction. |
| 10 (CTL1) | Control Input 1 | Paired with CTL2 to configure shutdown (both low) or ±4% margining (one high, one low). |
Key Features
| Feature | Design Value |
|---|---|
| Tiny circuit footprint | 0.19in² total solution size - achieved using 4.7µF ceramic input/output caps and 3.3µH inductor, ideal for space-constrained optical modules. |
| Ultra-low height | 1.8mm max component height - enables use in slim-profile telecom line cards and base station RF modules. |
| Integrated synchronous rectification | Eliminates external Schottky diode - improves efficiency by 5–10% at 1A and reduces thermal stress on PCB. |
| 100% duty-cycle operation | Enables regulation with VIN as low as VOUT + IOUT × (RDS(ON)P + RL) - critical for battery-powered DSL modems operating near end-of-life voltage. |
| Logic-controlled voltage margining | ±4% output offset via two TTL-compatible inputs - enables automated production test without external DACs or relays. |
Applications
| DSL Modem Power Rails | Optical Transceiver Core Supply |
|---|---|
Use Scenario: Providing stable 1.8V or 2.5V core voltage to ADSL/VDSL PHY ICs in residential gateways under varying AC adapter and PoE input conditions. IC Role / Device Role / Timing Role: Primary step-down regulator with fast transient response (<10µs recovery from 50% load step) to suppress noise coupling into analog front-end circuits. Use Value: 1.4MHz switching avoids interference with DSL upstream bands (25–138kHz), while ±1% accuracy ensures compliant signal integrity margins. | Use Scenario: Delivering tightly regulated 1.25V–2.5V bias to laser driver and TIA ICs in SFP+ and XFP optical modules operating at -40°C to +85°C. IC Role / Device Role / Timing Role: Compact, thermally robust DC/DC converter with 100% duty-cycle capability to maintain regulation during cold-start brownouts. Use Value: µMAX package's exposed PGND pad enables direct thermal coupling to metal housing, sustaining 1A output at full temperature range without derating. |
| DSP/ASIC Core Supply | Cellular Base Station Control Logic |
Use Scenario: Powering 1.8V or 2.5V cores of multi-GHz DSPs in wireless infrastructure equipment requiring low-noise, high-PSRR supply. IC Role / Device Role / Timing Role: High-bandwidth current-mode regulator with 140kHz loop bandwidth to reject high-frequency switching noise from adjacent RF sections. Use Value: Integrated slope compensation and transconductance amplifier eliminate need for complex Type II/III compensation, reducing BOM count by 2–3 passive components. | Use Scenario: Generating 1.8V logic supply for FPGAs and microcontrollers in distributed base station units deployed in outdoor cabinets. IC Role / Device Role / Timing Role: Robust, margin-test-ready power stage supporting automated factory calibration via CTL1/CTL2 voltage margining. Use Value: ±4% programmable output shift enables system-level validation of timing margins under worst-case voltage corners without hardware rework. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar step-down regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MAX1974EUB+ | Same 10-pin µMAX package and 1.4MHz architecture, but offers 1.0V/1.5V presets and 0.75V adjustable minimum; includes POK output instead of margining. | Used where power-good signaling is required (e.g., FPGA configuration sequencing), not voltage margin testing. | Select MAX1974EUB+ when POK functionality is needed and 1.0V/1.5V outputs match system requirements. |
| TPS62130ARGTR | 3–17V input, 3A output, 2.5MHz switching; no voltage margining; different pinout and compensation scheme. | Suitable for wider-input industrial applications but lacks logic-controlled margining and µMAX footprint. | Choose TPS62130ARGTR only if higher input voltage or output current is required and layout redesign is acceptable. |
Compared with MAX1974EUB+, the MAX1973EUB+ trades POK for voltage margining-making it uniquely suited for production test automation. Against TPS62130ARGTR, it offers smaller footprint and built-in test features at the cost of narrower input range and lower current rating.
Availability
MAX1973EUB+ is available at Aetrix Electronics and suitable for DSL modems, optical transceivers, DSP/ASIC core supplies, and cellular base station control logic requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for MAX1973EUB+ includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Maxim Integrated (now part of Analog Devices) designs precision analog, mixed-signal, and power management ICs for demanding industrial, telecom, and computing applications.
The MAX1973EUB+ belongs to Maxim's high-frequency step-down regulator product line, engineered specifically for space-constrained, high-reliability telecom and networking systems needing fast transient response and production-test-ready features like voltage margining.
FAQ
What is the maximum output current supported by the MAX1973EUB+?
The MAX1973EUB+ delivers up to 1A continuous output current under typical operating conditions (TA = +25°C, VIN = 3.3V). Its current-limit threshold is specified at 1.1–1.85A (min–max), and thermal shutdown activates at +170°C junction temperature. Derating is recommended above +70°C ambient due to 444mW power dissipation limit in the µMAX package.
Does the MAX1973EUB+ require external components for basic operation?
Yes - the MAX1973EUB+ requires an external inductor (2.2–4.7µH), input/output ceramic capacitors (4.7µF each), feedback resistors (if adjustable mode is used), and a soft-start capacitor (0.1µF for 6.25ms ramp). The COMP pin needs an RC network for loop compensation, and FBSEL must be tied to GND, IN, or left open depending on output voltage configuration.
How does voltage margining work on the MAX1973EUB+?
Voltage margining on the MAX1973EUB+ shifts the regulated output voltage by ±4% using two logic inputs (CTL1 and CTL2). With CTL1 = GND and CTL2 = IN, output increases +4%; with CTL1 = IN and CTL2 = GND, output decreases −4%. Both inputs high enable normal regulation; both low force shutdown. This feature is verified in production test setups for margin validation.
Can the MAX1973EUB+ operate with input voltage below 2.6V?
No - the MAX1973EUB+ has a guaranteed operating input range of 2.6V to 5.5V. Below 2.35V (typical undervoltage lockout threshold), the device disables switching and enters UVLO state. Operation below 2.6V is not characterized, and output regulation cannot be assured even if the part appears to function intermittently.
What package type and thermal characteristics does the MAX1973EUB+ use?
The MAX1973EUB+ uses a 10-pin µMAX package (3mm × 3mm × 0.8mm) with an exposed PGND pad for thermal conduction. Its continuous power dissipation is 444mW at TA = +70°C, derating 5.6mW/°C above that. Thermal shutdown triggers at +170°C junction temperature with 20°C hysteresis, ensuring robust protection during overload or poor heatsinking conditions.
MAX1973EUB+ Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Series:
- -
- Package/Case:
- 10-TFSOP, 10-MSOP (0.118", 3.00mm Width)
- Packaging:
- Tube
- Product Status:
- Active
- Function:
- Step-Down
- Output Configuration:
- Positive
- Topology:
- Buck
- Output Type:
- Adjustable (Programmable)
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 2.6V
- Voltage - Input (Max):
- 5.5V
- Voltage - Output (Min/Fixed):
- 0.75V (1.8V, 2.5V)
- Voltage - Output (Max):
- 5.5V
- Current - Output:
- 1A
- Frequency - Switching:
- 1.4MHz
- Synchronous Rectifier:
- Yes
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 10-uMAX/uSOP
MAX1973EUB+ FAQ
1.How can I place an order for MAX1973EUB+ through Aetrix?
Please submit a Request for Quotation (RFQ) for MAX1973EUB+ on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for MAX1973EUB+ reliable?
The price and inventory of MAX1973EUB+ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MAX1973EUB+ is usually 5 days.
3.What payment methods are accepted for MAX1973EUB+?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MAX1973EUB+ transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MAX1973EUB+?
MAX1973EUB+ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MAX1973EUB+ order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for MAX1973EUB+?
For technical support, including MAX1973EUB+ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MAX1973EUB+ requirements.
6.How does Aetrix verify that MAX1973EUB+ is sourced from the original manufacturer or authorized distributors?
All MAX1973EUB+ products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that MAX1973EUB+ meets industry standards.
7.What is the process for return or replacement of MAX1973EUB+?
All MAX1973EUB+ units undergo pre-shipment inspection (PSI). If there is an issue with MAX1973EUB+, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The MAX1973EUB+ part is unused and in its original packaging.
Return procedure for MAX1973EUB+:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MAX1973EUB+ Tags
-
TPS562201DDCR
Texas Instruments
-
MC34063ABD-TR
STMicroelectronics
-
TPS561201DDCR
Texas Instruments
-
MC33063ADR
Texas Instruments
-
MC34063ADR
Texas Instruments
-
TPS560200DBVR
Texas Instruments
-
AP3012KTR-G1
Diodes Incorporated
-
TLV61048DBVR
Texas Instruments
-
AZ34063UMTR-G1
Diodes Incorporated
-
TPS562200DDCR
Texas Instruments
-
AP62300TWU-7
Diodes Incorporated
-
MC34063EBD-TR
STMicroelectronics
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
