My Inquiry
My Account
Analog Devices Inc./Maxim Integrated MAX858CSA
- Part No.:
- MAX858CSA
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
MAX858CSA.pdf
- Description:
- IC REG BOOST PROG 125MA 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:2,324
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
MAX858CSA from Maxim Integrated is a high-efficiency, CMOS step-up DC-DC switching regulator optimized for low-input-voltage battery-powered systems. It accepts input voltages from 0.8V to VOUT, delivers pin-selectable 3.3V or 5V output, features 125mA peak inductor current limit, 25µA quiescent current, and operates in 8-pin SO package - enabling compact, long-life power conversion in glucose meters and portable data collectors.
For engineers reviewing the MAX858CSA datasheet, MAX858CSA pinout, MAX858CSA application, or MAX858CSA equivalent, this page provides verified technical context, real-world design meaning of key specs, validated pin functions, confirmed alternative options, and supply-chain support for industrial and medical embedded designs requiring ultra-low IQ and reliable 3.3V/5V boost conversion from single- or dual-cell batteries.
Technical Context
The MAX858CSA implements a minimum-off-time, current-limited pulse-frequency modulation (PFM) control scheme with no oscillator - switching frequency varies with load and input voltage up to 500kHz. Its internal N-channel sense-FET has ~4Ω on-resistance and 125mA ±25mA fixed peak switch-current limit, enabling use of small 47µH inductors without external compensation.
It integrates a precision 1.25V reference (±1.5% over temperature), low-battery detector (LBI/LBO) with 1.25V threshold and 25mV hysteresis, and internal bootstrapping via OUT pin - allowing operation down to 0.8V start-up voltage and sustaining regulation even as battery sags below VOUT.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | PIN-SELECTABLE: 3.3V (when 3/5 tied to OUT) or 5V (when 3/5 tied to GND); no external resistors needed |
| Input Voltage Range | 0.8V to VOUT; supports single-alkaline, single-LiFePO₄, or two-NiMH cells without pre-regulation |
| Peak Switch Current | 125mA ±25mA; sets inductor saturation margin and enables use of low-cost, miniature 47µH inductors |
| Quiescent Current | 25µA typical in active mode; ensures >1-year shelf life in battery-backed medical devices at light loads |
| Shutdown Current | 1µA max; reduces standby drain to negligible levels in always-on portable instrumentation |
| Reference Voltage | 1.25V ±1.5% over -40°C to +85°C; stable enough to drive ADC references or external comparators directly |
| Start-Up Voltage | 0.8V typical; allows cold-start from depleted batteries where other boosters fail to initiate |
Pinout & Package
MAX858CSA is housed in an 8-pin Small Outline (SO) package per JEDEC MS-012, 150-mil body width, with gull-wing leads and exposed pad not present. Pin 1 is marked by notch or dot; device orientation follows standard SO top-view convention.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 - LX | N-channel MOSFET drain | Switch node connecting to inductor; requires short, low-inductance PCB trace to minimize ringing and EMI |
| 2 - GND | Power ground | Must be soldered directly to solid ground plane; shared return for all high-current paths including LX and OUT |
| 3 - OUT | Regulator output / bootstrap supply | Delivers regulated 3.3V/5V; also powers internal circuitry - critical for start-up and stability |
| 4 - LBI | Low-battery input | Monitors battery voltage via resistor divider; triggers LBO when <1.25V; connect to VIN if unused |
| 5 - LBO | Open-drain low-battery output | Sinks current when LBI <1.25V; requires external pull-up (e.g., to OUT) for CMOS logic interface |
| 6 - REF | 1.25V precision reference output | Stable internal reference; bypass with 0.22µF to GND if loaded; max 250µA source / 20µA sink |
| 7 - 3/5 | Output voltage select | Tie to GND for 5V output, to OUT for 3.3V output; internally diode-clamped - must not exceed GND–OUT range |
| 8 - SHDN | Active-low shutdown control | Pulls entire IC into 1µA sleep; open-drain compatible up to 7V - safe for interfacing with higher-voltage logic |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-low quiescent current | 25µA active / 1µA shutdown - extends battery life in intermittent-use medical sensors and PDAs |
| Pin-selectable fixed output | No feedback resistors required for 3.3V/5V; eliminates BOM cost and layout error risk vs. adjustable variants |
| Integrated low-battery detection | Dedicated LBI/LBO pins with 1.25V threshold and 25mV hysteresis - enables system-level battery management without extra ICs |
| Internal sense-FET architecture | ~4Ω RDS(on) and 125mA peak current limit - permits use of low-profile, low-cost 47µH inductors (e.g., Sumida CDR74B-470) |
| 0.8V start-up capability | Operates from deeply discharged cells (e.g., 1.0V alkaline) - critical for glucose meters and handheld diagnostics |
Applications
| Glucose Monitoring Systems | Portable Data Collectors |
|---|---|
Use Scenario: Battery-powered handheld glucose meter operating from two AAA alkaline cells (1.0–3.0V range) with LCD, microcontroller, and electrochemical sensor. IC Role / Device Role: Primary 3.3V system rail generator; supplies MCU, display driver, and analog front-end from sagging battery. Use Value: 0.8V start-up ensures reliable operation even after extended storage; 25µA IQ preserves battery for >2 years in standby. |
Use Scenario: Ruggedized barcode scanner used in warehouse logistics, powered by rechargeable NiMH pack (1.2–1.8V/cell). IC Role / Device Role: Step-up converter delivering stable 5V to image sensor and USB interface IC. Use Value: 125mA peak current limit matches typical pulsed load profile; integrated LBO alerts host MCU before battery depletion. |
| Personal Digital Assistants | Medical Diagnostic Handhelds |
Use Scenario: Palm-sized PDA with monochrome LCD, flash memory, and IR transceiver, running on single LiFePO₄ cell (2.5–3.6V). IC Role / Device Role: Generates 3.3V logic rail from battery; coexists with 5V USB charging path. Use Value: Pin-selectable output avoids redesign when migrating between 3.3V and 5V peripheral configurations. |
Use Scenario: Portable ECG or pulse oximeter using coin-cell battery (1.5V) and low-power analog signal chain. IC Role / Device Role: Supplies clean 3.3V to precision ADC and op-amps while minimizing noise coupling. Use Value: PFM control yields low-noise, variable-frequency switching - less disruptive to sensitive analog measurements than PWM. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar step-up DC-DC converter applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MAX856CSA | 500mA peak switch current, 500mA output capability, 1Ω RDS(on), same 8-pin SO package | Higher output current (100mA vs. 35mA @ 3.3V); suited for systems with heavier pulsed loads | Select MAX856CSA when ≥100mA 3.3V/5V output is required; MAX858CSA preferred for ultra-low IQ and minimal inductor size in sub-50mA applications. |
| TPS61200DRCR | Adjustable output (1.8–5.5V), 1.2A switch current, 2.5µA IQ, 10-pin WSON package | Wider input range (0.3–5.5V), higher efficiency at mid-load, but requires external feedback resistors and lacks integrated LBI/LBO | Choose TPS61200DRCR for ultra-low-voltage start-up (<0.8V) or adjustable output flexibility; MAX858CSA retains advantage in simplicity, integrated monitoring, and proven medical-grade reliability. |
Compared with MAX856CSA and TPS61200DRCR, the MAX858CSA delivers optimal trade-off of ultra-low quiescent current, pin-strapped simplicity, and integrated battery monitoring - making it uniquely suitable for space-constrained, long-life, fixed-output medical and portable instrumentation where BOM count and standby drain are critical.
Availability
MAX858CSA is available at Aetrix Electronics and suitable for glucose meters, portable data collectors, personal digital assistants, and medical diagnostic handhelds requiring stable component supply with guaranteed long-term availability and full traceability.
Supply support for MAX858CSA 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, medical, and communications applications.
The MAX856–MAX859 family was designed specifically for ultra-low-power, battery-critical portable electronics - emphasizing sub-1V start-up, nanoampere shutdown, and integrated system monitoring to eliminate discrete support components.
FAQ
What output voltages does the MAX858CSA support, and how are they selected?
The MAX858CSA supports fixed 3.3V or 5V output, selected solely by the logic state of the 3/5 pin: tie to GND for 5V output, tie to OUT for 3.3V output. No external resistors or programming are required. This pin-strapped configuration ensures deterministic behavior and eliminates feedback network errors - a key advantage over adjustable regulators like the MAX857CSA or MAX859CSA.
What is the minimum input voltage required for the MAX858CSA to start switching?
The MAX858CSA has a typical start-up input voltage of 0.8V, verified across temperature and load conditions. This allows reliable cold-start from nearly depleted single-cell batteries (e.g., 1.0V alkaline or 2.0V LiFePO₄). The actual minimum depends on output load and target voltage - e.g., 0.85V at 25mA load for 5V output, per Figure MAX856-07 in the datasheet.
How does the MAX858CSA achieve ultra-low quiescent current, and what is its impact on battery life?
The MAX858CSA achieves 25µA typical quiescent current through a proprietary PFM control architecture that eliminates continuous oscillator operation and minimizes bias currents in internal comparators and references. At 10µA average system load, this translates to >3 years of operation on a 120mAh coin cell - directly enabling multi-year shelf life in glucose meters and remote sensors without maintenance.
Can the MAX858CSA drive a 100mA load at 5V output?
No - the MAX858CSA is rated for up to 35mA at 3.3V and 25mA at 5V under typical conditions (VIN = 2.5V), limited by its 125mA peak switch-current specification and ~4Ω internal MOSFET RDS(on). For 100mA 5V output, the pin-compatible MAX856CSA (500mA peak switch current) is the appropriate variant within the same family and package.
Does the MAX858CSA include integrated low-battery detection, and how is it configured?
Yes - the MAX858CSA integrates a dedicated low-battery comparator with LBI (input) and LBO (open-drain output) pins. LBI triggers at 1.25V ±25mV; connect a resistor divider from VIN to GND to set the detection threshold (e.g., 2.5V battery = R3/R4 = 1:1). LBO sinks current when triggered and requires an external pull-up to OUT or VCC - enabling direct interface with microcontroller GPIOs for battery-alert firmware handling.
MAX858CSA Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Function:
- Step-Up
- Output Configuration:
- Positive
- Topology:
- Boost
- Output Type:
- Programmable
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 0.8V
- Voltage - Input (Max):
- 6V
- Voltage - Output (Min/Fixed):
- 3.3V, 5V
- Voltage - Output (Max):
- -
- Current - Output:
- 125mA (Switch)
- Frequency - Switching:
- 500kHz
- Synchronous Rectifier:
- No
- Operating Temperature:
- 0°C ~ 70°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SOIC
MAX858CSA FAQ
1.How can I place an order for MAX858CSA through Aetrix?
Please submit a Request for Quotation (RFQ) for MAX858CSA 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 MAX858CSA reliable?
The price and inventory of MAX858CSA are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MAX858CSA is usually 5 days.
3.What payment methods are accepted for MAX858CSA?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MAX858CSA transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MAX858CSA?
MAX858CSA orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MAX858CSA 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 MAX858CSA?
For technical support, including MAX858CSA datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MAX858CSA requirements.
6.How does Aetrix verify that MAX858CSA is sourced from the original manufacturer or authorized distributors?
All MAX858CSA 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 MAX858CSA meets industry standards.
7.What is the process for return or replacement of MAX858CSA?
All MAX858CSA units undergo pre-shipment inspection (PSI). If there is an issue with MAX858CSA, 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 MAX858CSA part is unused and in its original packaging.
Return procedure for MAX858CSA:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MAX858CSA 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…
