HOT 1Pcs Mega 2560 R3 +1Pcs Ramps 1.4+5pcs A4988+5Pcs Heatsinks+1Pcs Cable + MK3 Alu- Heatbed For 3d Printer

HOT 1Pcs Mega 2560 R3 +1Pcs Ramps 1.4+5pcs A4988+5Pcs Heatsinks+1Pcs Cable + MK3 Alu- Heatbed For 3d Printer

Product Descriptio

Ramps

RepRap  Mega Pololu Shield, or RAMPS for short. It is designed to fit the entire electronics needed for a RepRap in one small package for low cost. RAMPS interfaces an Ard Mega with the powerful Ard MEGA platform and has plenty room for expansion. The modular design includes plug in stepper drivers and extruder control electronics on an Ard MEGA shield for easy service, part replacement, upgrade-ability and expansion. Additionally, a number of Ard expansion boards can be added to the system as long as the main RAMPS board is kept to the top of the stack.
Version 1.4 uses surface mount capacitors and resistors to further cover edge issue cases.

A4988

A4988 is a complete microstepping motor driver with built-in translator for easy operation. This product is available in full, half, 1/4, 1/8 and 1/16 step modes operate bipolar stepper motors, output drive capacity of up to 35 V and ± 2 A. A4988 includes a fixed off-time current regulator, the regulator in slow or mixed decay modes. A4988 converter is the key to the easy implementation. As long as the "step" input inputting one pulse drives the motor one microstep. There are no phase sequence tables, high frequency control lines, or complex interfaces to program. A4988 interface is very suitable for complex microprocessor is unavailable or is overburdened.

In the micro-step operation, A4988 chopping control inside automatically selects the current decay mode (Slow or Mixed). In mixed decay mode, the device is initially set to a fixed downtime in some fast decay, then the rest of the slow decay downtime. Mixed decay current control scheme results in reduced audible motor noise, increased step accuracy, and reduced power consumption. Internal synchronous rectification control circuitry is provided to improve the pulse-width modulation (PWM) operation power consumption. Internal circuit protection includes: thermal shutdown with hysteresis, undervoltage lockout (UVLO), and crossover-current protection. Special power sequencing.

A4988 surface mount QFN package (ES), a size of 5 mm × 5 mm, nominal overall package height of 0.90 mm, with an exposed pad for enhanced thermal dissipation. This package is Pb (suffix-T), with 100% matte tin leadframe plating.