My Inquiry
My Account
Analog Devices Inc./Maxim Integrated MAX868EUB+
- Part No.:
- MAX868EUB+
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Package:
- 10-TFSOP, 10-MSOP (0.118", 3.00mm Width)
- Datasheet:
-
MAX868EUB+.pdf
- Description:
- IC REG CHRG PUMP INV 30MA 10UMAX
- Quantity:
- Payment:
- Shipping:
Inventory:4,852
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
The MAX868EUB+ from Maxim Integrated is a regulated, adjustable -2× inverting charge pump IC that generates a stable negative output voltage up to -2 × VIN from a 1.8V–5.5V positive input, delivering up to 30mA output current with PFM control, 30µA quiescent supply current, and 0.1µA shutdown current-used in compact portable devices requiring efficient, inductorless negative rail generation.
For engineers reviewing the MAX868EUB+ datasheet, MAX868EUB+ pinout, MAX868EUB+ application, or MAX868EUB+ equivalent, key selection considerations include its 10-pin µMAX package footprint, -40°C to +85°C operating range, regulated feedback architecture (FB pin), on-demand 270–630kHz oscillator, and compatibility with ceramic flying/output capacitors for low-ripple, space-constrained designs.
Technical Context
The MAX868EUB+ implements pulse-frequency-modulation (PFM) control to gate a 450kHz internal oscillator on-demand-only activating switching during load transients or regulation error-to maintain output voltage while minimizing light-load current draw. Its dual-phase charge-pump topology alternates between parallel charging of C1/C2 and series discharge into COUT.
Regulation is achieved via external resistor divider on the FB pin (trip point ±40mV), enabling precise output setting down to -2×VIN; when FB is tied to IN, it operates as an open-loop doubler-inverter at maximum frequency. The device features separate PGND and GND pins to isolate power and analog return paths, reducing noise coupling.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 1.8V to 5.5V - supports single-cell Li-ion, NiMH, and regulated 3.3V/5V rails without external LDO pre-regulation. |
| Output Current | Up to 30mA - sufficient for biasing LCD VEE, op-amp dual supplies, or sensor interfaces in portable systems. |
| Quiescent Supply Current | 30µA - enables >1000-hour battery life in always-on low-power monitoring circuits. |
| Shutdown Current | 0.1µA - reduces standby drain to negligible levels in sleep-mode handheld instruments. |
| Oscillator Frequency | 270–630kHz - high-frequency operation allows use of sub-1µF ceramic flying capacitors, minimizing board area. |
| Feedback Trip Point | ±40mV - tight tolerance ensures ≤1% output voltage error across temperature with standard 1% resistors. |
| Open-Loop Output Resistance | 70Ω typical - defines load regulation slope (~2.1mV/mA) and sets minimum output capacitance for stability. |
Pinout & Package
The MAX868EUB+ is housed in a 10-pin µMAX package (3mm × 3mm, 1.11mm height), occupying half the PCB area of a standard 8-pin SOIC and optimized for ultra-compact portable layouts.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 - GND | Analog Ground | Reference node for FB comparator and internal bias circuitry; must be short-traced to PGND and system ground plane. |
| 2 - OUT | Charge-Pump Output | Negative regulated output terminal; connects to load and output capacitor (COUT); actively pulled to GND in shutdown. |
| 3 - C1- | Flying Capacitor C1 Negative Terminal | Switched node in Φ1/Φ2 phases; connects to one end of flying cap C1; requires low-ESR ceramic placement adjacent to pin. |
| 4 - PGND | Power Ground | High-current return path for internal switches; must be joined to GND with minimal trace length to reduce noise and dropout. |
| 5 - C1+ | Flying Capacitor C1 Positive Terminal | Switched node in Φ1/Φ2 phases; connects to other end of flying cap C1; forms part of charge/discharge path with C2. |
| 6 - C2- | Flying Capacitor C2 Negative Terminal | Switched node; connects to one end of flying cap C2; used in series configuration during discharge phase (Φ2). |
| 7 - IN | Supply-Voltage Input | Positive input rail (1.8V–5.5V); also serves as reference when FB is tied directly to IN for unregulated -2× operation. |
| 8 - C2+ | Flying Capacitor C2 Positive Terminal | Switched node; connects to other end of flying cap C2; completes flying-capacitor network with C1 for charge pumping. |
| 9 - SHDN | Active-Low Shutdown Input | Logic-controlled enable: GND = shutdown (0.1µA IIN), IN = active; OUT driven to GND during shutdown. |
| 10 - FB | Feedback Input | Connects to resistor divider for closed-loop regulation; ±50nA input bias allows use of >500kΩ resistors without accuracy loss. |
Key Features
| Feature | Design Value |
|---|---|
| Regulated -2× inverting output | Enables precise negative rail generation (e.g., -5V, -7.5V) from 3.3V/5V inputs using only two resistors-no external reference needed. |
| On-demand PFM switching | Reduces light-load current to 30µA while maintaining full 30mA capability-eliminates need for efficiency-compromising forced PWM modes. |
| Inductorless design | Uses four small ceramic capacitors only-removes EMI, size, and cost penalties associated with magnetic components in portable systems. |
| Ultra-small µMAX package | 3mm × 3mm footprint with 1.11mm profile fits within tight spacing constraints of PDAs, medical handhelds, and smart sensors. |
| Separate PGND/GND pins | Minimizes ground bounce and supply noise coupling into feedback path-critical for stable regulation under dynamic load conditions. |
Applications
| Small LCD Panels | Cell Phones |
|---|---|
|
Use Scenario: Generating VEE bias voltage for monochrome or color STN/TFT LCD displays requiring -3.3V to -7.5V rails. IC Role / Device Role / Timing Role: Regulated negative charge pump supplying stable VEE to display driver ICs, replacing discrete inductor-based solutions. Use Value: Enables <1mm board height and <10mm² total solution size while maintaining <±1% VEE accuracy across battery discharge (1.8V–5.5V VIN). |
Use Scenario: Providing negative supply for RF front-end amplifiers, audio codecs, or camera sensor bias in slim smartphone designs. IC Role / Device Role / Timing Role: Compact inductorless DC-DC converter generating clean -2.5V/-3.3V rails from main 3.3V/5V battery bus. Use Value: Achieves 75–85% efficiency at 10–20mA loads with <10mVpp ripple-meeting stringent noise requirements for sensitive analog signal chains. |
| Medical Handheld Instruments | Handheld Terminals & PDAs |
|
Use Scenario: Powering precision op-amps, ADC references, or isolated sensor interfaces in battery-operated glucose meters or ECG monitors. IC Role / Device Role / Timing Role: Low-quiescent, shutdown-capable negative rail generator ensuring long runtime and accurate analog signal conditioning. Use Value: Delivers 0.1µA shutdown current and ±40mV FB trip point-enabling >2-year shelf life and <0.5% measurement drift over temperature. |
Use Scenario: Supplying dual-rail power to microcontroller peripherals, touch-screen controllers, and memory interfaces in rugged industrial PDAs. IC Role / Device Role / Timing Role: Robust charge pump supporting -40°C to +85°C operation with integrated thermal protection and wide input range. Use Value: Maintains regulation across full battery range (3.0V–4.2V Li-ion) and survives cold-start conditions without brownout or latch-up. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar inverting charge pump applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MAX868C/D | Same silicon die but rated for 0°C to +70°C ambient; no internal temp sensor; lower max junction temp rating. | Suitable only for commercial-grade indoor applications-not rated for extended automotive or industrial temperature cycling. | Select MAX868C/D only if operating environment stays within 0°C–70°C and cost sensitivity outweighs reliability margin. |
| TPS60403DBVR | Texas Instruments' 30mA inverting charge pump with fixed -3.3V output; no FB pin; 2.7–5.5V input; 1.5µA quiescent current. | Lacks adjustable output-requires redesign if -5V or -7.5V rails are needed; simpler BOM but less flexible for multi-voltage systems. | Choose TPS60403DBVR only for fixed -3.3V applications where lowest possible IQ is critical and output adjustability is unnecessary. |
Compared with MAX868C/D, the MAX868EUB+ offers wider temperature coverage (-40°C to +85°C) and guaranteed performance at extremes, while versus TPS60403DBVR it provides adjustable output and tighter FB tolerance at the cost of higher quiescent current-making it optimal for field-deployed, multi-rail, or precision-bias applications.
Availability
MAX868EUB+ is available at Aetrix Electronics and suitable for medical handheld instruments, portable LCD panels, and industrial PDAs requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for MAX868EUB+ 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) is a U.S.-based semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, communications, and consumer applications.
The MAX868EUB+ belongs to Maxim's charge pump DC-DC converter product line, designed specifically for space-constrained, battery-powered systems needing clean, regulated negative rails without inductors or complex layout.
FAQ
What is the operating temperature range of the MAX868EUB+?
The MAX868EUB+ is specified for continuous operation from -40°C to +85°C ambient temperature. This extended range is validated across electrical parameters including oscillator frequency (270–630kHz), FB trip point (±40mV), and output current capability (30mA), making it suitable for industrial and outdoor portable equipment where thermal stress is expected. The MAX868EUB+ part number explicitly denotes this grade-distinct from the MAX868C/D (0°C to +70°C) variant.
How do I configure the MAX868EUB+ for a regulated -5V output from a 3.3V input?
To set a regulated -5V output with the MAX868EUB+, connect the FB pin to a resistor divider between OUT and GND. Using the equation R1/R2 = |VOUT|/VREF and selecting VREF = VIN = 3.3V, choose R2 = 200kΩ and calculate R1 ≈ 303kΩ (standard 301kΩ 1% resistor). Place both resistors adjacent to the FB pin with short traces, and use 0.1µF ceramic flying caps (C1/C2) plus a 10µF X7R ceramic COUT for optimal ripple and stability. The MAX868EUB+'s ±40mV FB trip point ensures <1.2% output error at room temperature.
Can the MAX868EUB+ operate without external resistors?
Yes-the MAX868EUB+ can operate without external feedback resistors by connecting the FB pin directly to the IN pin. In this configuration, it functions as an unregulated -2× inverting charge pump (e.g., -6.6V from 3.3V input), running at maximum oscillator frequency (up to 630kHz) with no closed-loop control. Output voltage will vary with input and load due to open-loop output resistance (~70Ω), so this mode is appropriate only for non-critical biasing where exact voltage is not required. The MAX868EUB+ retains all other specs-including 30mA capability and 0.1µA shutdown-in this mode.
What capacitor types are recommended for the MAX868EUB+ flying and output stages?
For the MAX868EUB+, X7R-type surface-mount ceramic capacitors are strongly recommended for both flying (C1/C2) and output (COUT) stages due to their low ESR, stable capacitance over temperature, and compact size. Typical values are 0.1µF–0.22µF for C1/C2 and ≥10µF for COUT (≥10× flying cap value). Tantalum (e.g., AVX TPS series) is acceptable for COUT if low-ESR is maintained, but ceramics are preferred for ripple suppression and reliability. Avoid Y5V/Z5U dielectrics due to severe capacitance loss at temperature/voltage extremes-this directly impacts MAX868EUB+ load regulation and startup behavior.
Does the MAX868EUB+ require special PCB layout considerations?
Yes-the MAX868EUB+ demands careful layout to ensure stability and low noise. Key practices include: (1) joining GND and PGND pins with the shortest possible trace (<2mm) and connecting both to a solid ground plane; (2) placing all capacitors (C1, C2, CIN, COUT) within 3mm of their respective pins; (3) routing FB traces as short and shielded as possible-locate R1/R2 directly adjacent to FB; and (4) avoiding routing noisy signals (e.g., digital clocks) beneath the µMAX footprint. These steps minimize parasitic inductance/resistance that could degrade MAX868EUB+ regulation accuracy or cause oscillation.
MAX868EUB+ 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:
- Ratiometric
- Output Configuration:
- Negative
- Topology:
- Charge Pump
- Output Type:
- Adjustable (Programmable)
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 1.8V
- Voltage - Input (Max):
- 5.5V
- Voltage - Output (Min/Fixed):
- -Vin, -2Vin
- Voltage - Output (Max):
- -2Vin
- Current - Output:
- 30mA
- Frequency - Switching:
- 270kHz ~ 630kHz
- Synchronous Rectifier:
- No
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 10-uMAX/uSOP
MAX868EUB+ FAQ
1.How can I place an order for MAX868EUB+ through Aetrix?
Please submit a Request for Quotation (RFQ) for MAX868EUB+ 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 MAX868EUB+ reliable?
The price and inventory of MAX868EUB+ are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MAX868EUB+ is usually 5 days.
3.What payment methods are accepted for MAX868EUB+?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MAX868EUB+ transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MAX868EUB+?
MAX868EUB+ orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MAX868EUB+ 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 MAX868EUB+?
For technical support, including MAX868EUB+ datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MAX868EUB+ requirements.
6.How does Aetrix verify that MAX868EUB+ is sourced from the original manufacturer or authorized distributors?
All MAX868EUB+ 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 MAX868EUB+ meets industry standards.
7.What is the process for return or replacement of MAX868EUB+?
All MAX868EUB+ units undergo pre-shipment inspection (PSI). If there is an issue with MAX868EUB+, 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 MAX868EUB+ part is unused and in its original packaging.
Return procedure for MAX868EUB+:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MAX868EUB+ 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…
