My Inquiry
My Account
Allegro MicroSystems A4956KLPTR-T
- Part No.:
- A4956KLPTR-T
- Manufacturer:
- Allegro MicroSystems
- Category:
- Motor Drivers, Controllers
- Package:
- 20-TSSOP (0.173", 4.40mm Width) Exposed Pad
- Datasheet:
-
A4956KLPTR-T.pdf
- Description:
- IC MOTOR DRIVER 5.5V-50V 20TSSOP
- Quantity:
- Payment:
- Shipping:
Inventory:8,000
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
A4956KLPTR-T from Allegro MicroSystems is a full-bridge PWM gate driver IC designed for external N-channel MOSFET H-bridges in DC motor control systems. It supports 50 V operation, provides synchronous rectification, adjustable off-time and blank-time (via RC network), programmable current limit (via VREF and sense resistor), and integrated VDS protection. It is used in industrial motion control systems requiring high-temperature operation up to 125°C ambient.
For engineers reviewing the A4956KLPTR-T datasheet, A4956KLPTR-T pinout, A4956KLPTR-T application, or A4956KLPTR-T equivalent, key selection considerations include its eTSSOP-20 LP package with exposed thermal pad, –40°C to 125°C operating range, AEC-Q100 qualification, and NOT FOR NEW DESIGN status effective July 2019.
Technical Context
The A4956KLPTR-T implements fixed off-time PWM current regulation using an external sense resistor and VREF input, with peak current calculated as IPEAK = VREF / (10 × RSENSE). It features dual decay mode selection (slow/fast/mixed) via MODE pin and internal synchronous rectification to reduce conduction losses during PWM off-times.
Its gate drive architecture uses a charge pump to generate high-side gate voltage above VBB, supporting all-N-channel MOSFET bridges. Protection functions include VDS monitoring (trip threshold 2 V), thermal shutdown at 150–185°C with 30°C hysteresis, UVLO (5.1–5.4 V enable threshold), and crossover-current prevention via 1 µs dead time.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VBB Max | 50 V - Enables direct interface with 48 V industrial bus systems without level-shifting. |
| Operating Temp | –40°C to +125°C - Qualified for under-hood automotive and high-temp industrial environments. |
| Package | eTSSOP-20 with exposed thermal pad - Provides 28°C/W junction-to-ambient thermal resistance on 4-layer PCB. |
| Gate Drive Current | Pull-down: 47–89 mA; Pull-up: 21–39 mA - Sufficient to drive 10 nC gate charge MOSFETs at >20 kHz PWM. |
| Current Sensing | AIOUT gain = 10 V/V, offset ≤ ±15 mV - Enables accurate real-time motor current monitoring with 50–200 mV sense range. |
| Protection Features | VDS fault detection (2 V threshold), thermal shutdown (150–185°C), UVLO (5.25 V ±150 mV), OCLn open-drain flag - Enables autonomous fault response without host intervention. |
| Decay Control | Mixed-decay mode with 13% fast-decay portion - Reduces torque ripple while limiting back-EMF-induced current reversal. |
Pinout & Package
The A4956KLPTR-T is supplied in a 20-lead eTSSOP package (suffix "LP") with exposed thermal pad, optimized for thermal performance in high-power motor drive applications.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| ISET | Gate drive current programming | Resistor to GND sets HS/LS gate drive strength (RISET = 15–150 kΩ yields 3.5–100 mA LS pull-down). |
| MODE | Decay mode selection | Logic high enables slow-decay (braking); low enables fast/mixed decay for dynamic speed control. |
| SENSE | Current sense return | Connects to low-side shunt resistor; referenced to GLA/GLB for bidirectional current sensing. |
| GLA/GLB | Low-side gate drivers | Drive N-MOSFET sources; support synchronous rectification during off-time. |
| GHA/GHB | High-side gate drivers | Charge-pump-powered outputs driving N-MOSFET drains; require external bootstrap or charge pump caps. |
| SB/SA | High-side bridge references | Provide local ground references for high-side drivers; connect to respective MOSFET source terminals. |
| VCP | Charge pump reservoir | Connects to 0.1 µF capacitor; supplies boosted voltage for high-side gate drive above VBB. |
| CP1/CP2 | Charge pump terminals | Internal flying-capacitor nodes; CP1 connects to VCP, CP2 to GND for charge pump operation. |
| VBB | Main supply input | 5.5–50 V power rail; powers logic, gate drivers, and charge pump; monitored for UVLO. |
| GND | Power and signal ground | Common reference for all analog/digital circuits; must be low-impedance connection to thermal pad. |
| AIOUT | Analog current monitor | 10× amplified VSENSE output; holds sampled value during blanking; droop rate ≤1 mV/µs. |
| OCLn | Open-drain fault flag | Drives low on overcurrent (tOCLn = 300–600 µs timeout) or VDS fault; requires external pull-up. |
| VREF | Current limit reference | Analog input (0–2.5 V) setting peak current threshold; IVREF < ±5 µA ensures stable regulation. |
| ENABLE | Enable/standby control | Logic high enables operation; held low >1 ms enters standby (IBB < 5 µA). |
| PHASE | Direction control | Controls H-bridge polarity: PHASE = 1 + ENABLE = 1 → forward; PHASE = 0 + ENABLE = 1 → reverse. |
| RC | Timing network node | Resistor+capacitor to GND sets tOFF (30 µs typ.) and tBLK (3 µs typ.) for PWM current regulation. |
Key Features
| Feature | Design Value |
|---|---|
| Synchronous rectification | Reduces power dissipation by enabling low-side MOSFET conduction during off-time instead of freewheeling diode loss. |
| Adjustable current limit | VREF input (0–2.5 V) and external RSENSE allow precise, software-tunable peak current setting without hardware changes. |
| Mixed-decay PWM control | Automatically applies 13% fast decay followed by slow decay during off-time to minimize torque ripple and acoustic noise. |
| VDS fault protection | Monitors MOSFET VDS in real time with blanking synchronized to switching edges; latches off on >2 V fault. |
| Thermal shutdown with hysteresis | Disables outputs at 150–185°C junction temperature and remains off until die cools by ≥30°C, preventing thermal cycling. |
Applications
| Industrial Conveyor Systems | Automotive HVAC Blower Motors |
|---|---|
Use Scenario: Precise speed and direction control of belt-driven conveyor belts in factory automation lines operating continuously at elevated ambient temperatures. IC Role / Device Role / Timing Role: Full-bridge gate driver controlling external N-MOSFET H-bridge; regulates motor current via fixed off-time PWM and provides real-time AIOUT feedback for closed-loop torque control. Use Value: Enables reliable 125°C ambient operation with thermal shutdown and VDS protection, reducing field failures in unventilated enclosures. | Use Scenario: Variable-speed blower motor control in automotive climate control systems requiring AEC-Q100 compliance and robust fault handling. IC Role / Device Role / Timing Role: Gate driver implementing mixed-decay PWM to minimize audible noise during low-speed airflow modulation; OCLn flag alerts ECU to stall or short-circuit faults. Use Value: AEC-Q100 qualification and integrated diagnostics (VDS, thermal, UVLO) eliminate need for external fault monitoring circuitry. |
| Medical Infusion Pumps | Robot Joint Actuators |
Use Scenario: Low-noise, high-precision DC motor control in battery-powered infusion pumps where current accuracy and fault safety are critical. IC Role / Device Role / Timing Role: Current-regulated H-bridge driver using VREF and RSENSE to maintain ±2% flow rate accuracy; AIOUT provides continuous current telemetry to MCU. Use Value: Adjustable blank-time prevents false overcurrent trips from switching transients, ensuring uninterrupted drug delivery. | Use Scenario: Compact, high-torque joint motor drivers in collaborative robots requiring rapid acceleration/deceleration and regenerative braking. IC Role / Device Role / Timing Role: Full-bridge controller supporting both forward/reverse motion and active braking via MODE-selectable decay modes. Use Value: Synchronous rectification and mixed-decay mode reduce heat generation during frequent direction reversals, extending MOSFET lifetime. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar full-bridge gate driver applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TB9051FTG | Integrated half-bridge drivers with embedded N-MOSFETs (40 V max); no external MOSFET requirement; SPI interface for configuration. | Lower BOM count but limited to ≤40 V and <5 A continuous; unsuitable for high-power industrial motors. | Select when system-level integration and digital configurability outweigh need for 50 V rating and external MOSFET flexibility. |
| MP6532DS-LF-Z | 40 V max, 200 kHz max PWM frequency, no VDS monitoring; thermal shutdown only; QFN-24 package. | Lacks VDS fault detection and mixed-decay mode; lower thermal performance (RθJA = 42°C/W vs. 28°C/W). | Consider only for cost-sensitive, non-safety-critical 40 V applications where AEC-Q100 and advanced protection are not required. |
Compared with TB9051FTG and MP6532DS-LF-Z, the A4956KLPTR-T offers higher 50 V operation, VDS fault latching, AEC-Q100 qualification, and superior thermal resistance-making it suitable for demanding industrial and automotive applications despite its NOT FOR NEW DESIGN status.
Availability
A4956KLPTR-T is available at Aetrix Electronics and suitable for industrial motor drives, automotive HVAC systems, and medical infusion pumps requiring stable component supply under extended temperature and reliability constraints.
Supply support for A4956KLPTR-T 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
Allegro MicroSystems is a U.S.-based semiconductor company specializing in magnetic sensing, power ICs, and motor control solutions since 1989.
The A4956 product line delivers high-voltage, thermally robust gate drivers for external N-MOSFET H-bridges in automotive, industrial, and medical motion control applications requiring functional safety and long-term reliability.
FAQ
What does "NOT FOR NEW DESIGN" mean for the A4956KLPTR-T?
The A4956KLPTR-T was classified NOT FOR NEW DESIGN effective July 1, 2019. This means Allegro no longer recommends it for newly initiated projects due to probable near-term obsolescence. However, Aetrix Electronics continues to supply the A4956KLPTR-T for existing customer applications with full traceability and lifecycle coordination support.
Does the A4956KLPTR-T support both fast and slow decay modes?
Yes, the A4956KLPTR-T supports selectable decay modes via the MODE pin: logic high enables slow decay (braking), logic low enables fast or mixed decay. In mixed-decay mode-activated during internal PWM current limiting-the A4956KLPTR-T applies 13% fast decay followed by slow decay for the remainder of the off-time.
How is current limiting implemented in the A4956KLPTR-T?
The A4956KLPTR-T implements peak current limiting using fixed off-time PWM control. The peak current is set by IPEAK = VREF / (10 × RSENSE). When VSENSE exceeds VREF/10, the high-side driver turns off for a programmable tOFF (set by RC network), initiating decay. This occurs independently for each half-bridge leg.
What thermal performance can be expected from the A4956KLPTR-T in its eTSSOP package?
The A4956KLPTR-T in the 20-pin eTSSOP (LP) package achieves a junction-to-ambient thermal resistance (RθJA) of 28°C/W on a 4-layer PCB with 1 in² copper. This allows sustained operation at full load up to 125°C ambient when properly mounted with thermal vias under the exposed pad.
Can the A4956KLPTR-T be used without an external sense resistor?
No-the A4956KLPTR-T requires an external sense resistor connected between SENSE and GND to implement current regulation and protection. The device measures voltage across this resistor to derive motor current; omitting it disables overcurrent protection, AIOUT monitoring, and internal PWM current limiting functionality of the A4956KLPTR-T.
A4956KLPTR-T Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Allegro MicroSystems
- Series:
- -
- Package/Case:
- 20-TSSOP (0.173", 4.40mm Width) Exposed Pad
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Not For New Designs
- Motor Type - Stepper:
- -
- Motor Type - AC, DC:
- Brushed DC
- Function:
- Controller - Commutation, Direction Management
- Output Configuration:
- Pre-Driver - Half Bridge (2)
- Interface:
- Parallel
- Technology:
- NMOS
- Step Resolution:
- -
- Applications:
- General Purpose
- Current - Output:
- -
- Voltage - Supply:
- 5.5V ~ 50V
- Voltage - Load:
- -
- Operating Temperature:
- -40°C ~ 125°C (TA)
- Grade:
- Automotive
- Qualification:
- AEC-Q100
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 20-TSSOP-EP
A4956KLPTR-T FAQ
1.How can I place an order for A4956KLPTR-T through Aetrix?
Please submit a Request for Quotation (RFQ) for A4956KLPTR-T 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 A4956KLPTR-T reliable?
The price and inventory of A4956KLPTR-T are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for A4956KLPTR-T is usually 5 days.
3.What payment methods are accepted for A4956KLPTR-T?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for A4956KLPTR-T transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for A4956KLPTR-T?
A4956KLPTR-T orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your A4956KLPTR-T 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 A4956KLPTR-T?
For technical support, including A4956KLPTR-T datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your A4956KLPTR-T requirements.
6.How does Aetrix verify that A4956KLPTR-T is sourced from the original manufacturer or authorized distributors?
All A4956KLPTR-T 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 A4956KLPTR-T meets industry standards.
7.What is the process for return or replacement of A4956KLPTR-T?
All A4956KLPTR-T units undergo pre-shipment inspection (PSI). If there is an issue with A4956KLPTR-T, 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 A4956KLPTR-T part is unused and in its original packaging.
Return procedure for A4956KLPTR-T:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
A4956KLPTR-T Tags
-
DRV2603RUNR
Texas Instruments
-
DRV8837CDSGR
Texas Instruments
-
DRV8837DSGR
Texas Instruments
-
DRV8838DSGR
Texas Instruments
-
DRV8839DSSR
Texas Instruments
-
EMC2301-1-ACZL-TR
Microchip Technology
-
DRV8231ADSGR
Texas Instruments
-
EMC2302-2-AIZL-TR
Microchip Technology
-
DRV8800PWPR
Texas Instruments
-
DRV8835DSSR
Texas Instruments
-
EMC2303-1-KP-TR
Microchip Technology
-
DRV8876PWPR
Texas Instruments
Tech Hub
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
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…
