Loads on click. Unloads when scrolled away or the tab is hidden.

Symbol & Footprint

Schematic Symbol

Open full view ↗
Loads on click. Unloads when scrolled away or the tab is hidden.

PCB Footprint

Open full view ↗
Loads on click. Unloads when scrolled away or the tab is hidden.
Loads on click. Unloads when scrolled away or the tab is hidden.
Download PDF
Contents

README

markdown

HR8825

Jiaxing Heroic Elec Tech · Stepper Motor Driver · HTSSOP-28-EP

HR8825 from Jiaxing Heroic Elec Tech, in a HTSSOP-28-EP. Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin Name Type Function
1 CP1 passive Charge pump flying capacitor terminal 1. Connect a 0.1uF capacitor between CP1 and CP2 to build the high-side gate drive charge pump.
2 CP2 passive Charge pump flying capacitor terminal 2. Pairs with CP1 via a 0.1uF capacitor for internal charge pump generation.
3 VCP power_out Charge pump reservoir / high-side gate drive supply. Connect a 0.1uF capacitor from VCP to VM.
4 VMA power_in A-bridge motor supply, 8V to 32V. All VM pins must be tied together and bypassed to GND (≥100uF bulk plus 0.1uF ceramic close to pin).
5 AOUT1 output A-bridge H-bridge output 1. Connects to one terminal of the stepper motor A-phase coil. Rated ±2.5A (positive current is defined as AOUT1 → AOUT2).
6 ISENA passive A-bridge current-sense return. Connect the A-bridge sense resistor Rs from ISENA to GND; VTRIP is regulated to VAVREF/5.
7 AOUT2 output A-bridge H-bridge output 2. Connects to the other terminal of the stepper motor A-phase coil.
8 BOUT2 output B-bridge H-bridge output 2. Connects to one terminal of the stepper motor B-phase coil. Positive current direction is BOUT1 → BOUT2.
9 ISENB passive B-bridge current-sense return. Connect the B-bridge sense resistor Rs from ISENB to GND.
10 BOUT1 output B-bridge H-bridge output 1. Connects to the other terminal of the stepper motor B-phase coil.
11 VMB power_in B-bridge motor supply, 8V to 32V. Must be tied to VMA - all VM pins connect to the same supply.
12 AVREF input A-bridge current-set reference input, 1V to 3.5V (VREF absolute max -0.3 to 4V). Chopping current ICHOP = VAVREF / (5·Rs). Typically tied to BVREF and to V3P3OUT via a divider with 0.1uF bypass.
13 BVREF input B-bridge current-set reference input, 1V to 3.5V. Usually tied to AVREF so both bridges share the same reference.
14 GND power_in Device ground. All GND pins and the exposed thermal pad must be tied to the PCB ground plane.
15 V3P3OUT power_out Internal 3.3V LDO output (3.1V min / 3.5V max, up to 1mA load). Bypass with 0.1uF to GND; may be used to bias VREF and pull-ups.
16 nRESET input Active-low reset input. Low resets internal logic and sets the microstep indexer to HOME while disabling H-bridges; STEP inputs are ignored. Internal 100kΩ pull-down.
17 nSLEEP input Active-low sleep input. Low enters low-power sleep (H-bridges, charge pump and V3P3OUT disabled). On rising edge wait tWAKE ≈ 1ms before applying STEP. Internal 100kΩ pull-down.
18 nFAULT output Open-drain fault output. Pulled low on overcurrent (OCP) or thermal shutdown (TSD). Requires external pull-up (e.g. 10kΩ to V3P3OUT). VOL = 0.35V typ at 5mA.
19 DECAY input Decay-mode select. Tied low = slow-rise mixed-decay fall (~25us); left floating or high = full mixed decay. External pull-down resistor (22k-100k) trims decay time. Internal 22kΩ pull-down.
20 DIR input Direction control input. Sets the direction advanced by the internal microstep indexer on each STEP rising edge. Internal 100kΩ pull-down.
21 nENBL input Active-low output enable. Low enables the H-bridge outputs; high tri-states the outputs while the indexer continues to track STEP. Internal 100kΩ pull-down.
22 STEP input Step clock input. Rising edge advances the microstep indexer by one step. fSTEP up to 250kHz; tWH/tWL ≥ 1.9us. Internal 100kΩ pull-down.
23 NC unconnected No connect. Leave floating (no defined function).
24 MODE0 input Microstep resolution select bit 0. MODE[2:0] selects full/1/2/1/4/1/8/1/16/1/32-step operation per Table 1. Internal 100kΩ pull-down.
25 MODE1 input Microstep resolution select bit 1. See MODE0. Internal 100kΩ pull-down.
26 MODE2 input Microstep resolution select bit 2 (MSB). See MODE0. Internal 100kΩ pull-down.
27 nHOME output Open-drain HOME status output. Asserted low when the internal microstep indexer is at HOME position. Requires external pull-up.
28 GND power_in Device ground (second GND pin). Must be tied together with pin 14 GND and the exposed thermal pad (PPAD).
PPAD GND power_in Exposed thermal pad on the underside of the ETSSOP-28 package. Must be soldered to the ground plane for both electrical and thermal performance.

Key specifications

Parameter Value
Manufacturer Jiaxing Heroic Elec Tech
Package HTSSOP-28-EP
Category Motor Driver ICs
Pins 29

Ordering variants

Same part, different packaging or reel option.

  • HR8825MTER
  • HR8825MTERA

CAD (KiCad official)

  • Symbol: HR8825
  • Footprint: Package_SO:HTSSOP-28-1EP_4.4x9.7mm_P0.65mm_EP3.4x9.5mm
  • 3D model: HTSSOP-28-EP (KiCad packages3D, STEP)

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

  • Datasheet: Jiaxing Heroic Elec Tech datasheet (19 pp, sha256 91d3f5799f038978, retrieved 2026-08-17, tier: lcsc)
  • Datasheet language: Chinese. Pin names, descriptions, and specs on this page were extracted and translated to English by ds2sf; the linked PDF is the manufacturer original.
  • Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
  • CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF