Series specification · Digital DC-DC

2828x-240x Digital Power Module

1/8 brick · 28 V nominal bus · 28 V / 240 W nominal output

Selection input range: 18–36 V DC
Nominal output: 28 V DC
Rated power: 240 W
Source revision: 2025V2

Confirm specs / request quotation market@jingmusecurity.com

x characters are series placeholders, not complete order codes. Figures below are transcribed from supplied 2025V2 documents, reviewed on 2026-10-30; they are not independent Jingmu test results or certification. Confirm current specifications, cooling and derating. No original product-file downloads or uploads are offered.

Electrical and environmental specifications

Values retain source units, defaults and grade distinctions. Maximum current, adjusted output voltage, power and temperature limits are not necessarily simultaneously achievable. Typical efficiency is not a guaranteed minimum. Isolation values alone do not establish a safety approval or test duration.

Input specifications
Parameter	Source specification
Input enable *1 · On	RC shorted to −IN
Input enable *1 · Off	RC open relative to −IN
Transient input	60Vdc/100ms
No-load input current, Vin=28V · Enable on	I_in≤0.15A
No-load input current, Vin=28V · Enable off	I_in≤0.02A
Minimum input capacitance	220μF

Isolation specifications
Parameter	Source specification
Dielectric withstand · Input–output	1500Vdc
Dielectric withstand · Input–case	500Vdc
Dielectric withstand · Output–case	500Vdc
Insulation resistance · DC500V	200MΩ
Isolation capacitance	4700pF

Output specifications
Parameter	Source specification
Output voltage accuracy	±0.5%
Output voltage adjustment *3	-80%~+10%
Line regulation	±0.5%max
Load regulation	±0.5%max
Maximum output current	9A
Dynamic load response, 0% → 100% → 0%	±3%∙Vout
Ripple & noise (full load)	≤0.5%∙Vout
Soft-start time (default)	30ms±5%
Soft-start adjustment	30ms~10s
Short-circuit protection	Hiccup / auto-recovery
Overcurrent protection (default)	110% Io_max / auto-recovery, hiccup
Overcurrent adjustment *4	Adjustable within 0%–110% Io_max
Overvoltage protection	130% · Vo_nom / latched shutdown
Minimum output capacitance	220μF

General specifications
Parameter	Source specification
Conversion efficiency (typical)	94.2%
Switching frequency	400KHz
Storage temperature · I grade	-55℃~+100℃
Storage temperature · M grade	-60℃~+125℃
Operating temperature · I grade	-40℃~+85℃
Operating temperature · M grade	-55℃~+105℃
Overtemperature protection (default) · I grade	+90℃
Overtemperature protection (default) · M grade	+110℃
Overtemperature adjustment *5	Adjustable within the operating temperature range
Output enable *2	TTL positive / negative logic
Relative humidity	95%RH
Weight	≤60g

Documented digital functions and construction

59.0×25.0×13.5 mm / 2.32×0.98×0.53 in
PMBus digital interface
Phase-shifted full bridge with synchronous rectification
Adaptive-algorithm loop control (source description)
Input-side enable control
Output-side enable control
Runtime parameter configuration
Operating-data telemetry
Five-sided metal enclosure
Soft-start adjustment
Settings: output voltage, overcurrent threshold, overtemperature threshold and soft-start rise time
Telemetry: input voltage, output voltage, output current and temperature
Fault indication
Power-good indication
Startup discharge of residual output-capacitor charge (source description; verify sequencing)

Telemetry and configurable thresholds can support repeatable commissioning and fault diagnosis. These are integration benefits, not evidence of universally better efficiency, ripple or transient response than analog designs. Confirm PMBus commands, levels, timing, readback accuracy and firmware for the selected order code.

Source ordering table and enable grades

P / N distinguish positive / negative output-enable logic; I / M distinguish source temperature grades, not certifications. These are source-listed variants, not stock or qualification commitments. Scroll this table horizontally on small screens.

2828x-240x Ordering table
Source order code	Input (V DC)	Output (V DC)	Power (W)	Case temperature	Output enable logic
2828P-240I	18~36	28	240	-40℃~+85℃	Positive logic
2828P-240M	18~36	28	240	-55℃~+105℃	Positive logic
2828N-240I	18~36	28	240	-40℃~+85℃	Negative logic
2828N-240M	18~36	28	240	-55℃~+105℃	Negative logic

Pin definitions

Pin numbers and functions do not establish physical orientation, voltage tolerance, pull-ups or timing. Request the current bottom-view drawing and interface electrical specification before connecting a host.

2828x-240x Pin definitions
Pin	Name	Function
+IN	Positive input	Input positive
-IN	Negative input	Input negative
RC	Input enable	On: RC shorted to −IN; off: RC floating
+OUT	Positive output	Output positive
-OUT	Negative output	Output negative
1、2、3、4	Unused	Not used; leave floating
5	PMBus_CLK	PMBus clock: parameter read/write
6	PMB_DAT	PMBus data: parameter read/write
7	PGOOD	Output-ready indication: high means ready
8	Unused	Not used; leave floating
9	PMB_ALT	Fault alert: low indicates a fault
10	EN	Output enable

Application and parameter configuration

Input voltage range

Application section: rated input 18~36V; stated outer shutdown range 16~38V. The latter is not a recommended continuous operating or surge range.

Source accuracy note: output accuracy may degrade outside 18~36V. Reconcile any differences with the selection and ordering tables before design.

External input and output capacitors

External minimum input capacitance C_in=220μF. Source calls for low-ESR electrolytics and allowance for capacitance loss at low temperature.

External minimum output capacitance C_out=220μF. Source calls for low-ESR electrolytics and allowance for capacitance loss at low temperature.

Enable control

RC input enable and EN output enable are independent. Input enable must be on before output-side enable can control the output.

Input enable: short RC to −IN to turn on; leave RC open relative to −IN to turn off.

Positive output-enable logic: EN floating or high relative to OUT− = on; low / shorted to OUT− = off. Source-listed codes: 2828P-240I、2828P-240M. Verify any order-code discrepancy above.

Negative output-enable logic: EN floating or low relative to OUT− = on; high = off. Source-listed codes: 2828N-240I、2828N-240M. Verify any order-code discrepancy above.

Programming and monitoring workflow

The supplied application section describes a USB programmer and host monitoring software, online / offline configuration, retained settings and operating-data display. Parameters outside the model's allowed range are rejected. Verify programmer availability, firmware, commands and power-cycle/readback behavior; software and remote/cloud management are not promised as standard inclusions.

Source conditions and confirmation items

Efficiency, ripple and transient table values lack a complete temperature, cooling, probe / bandwidth and load-slew test matrix. Obtain model-specific conditions before acceptance testing.
Case-temperature grades are not ambient full-power ratings. Confirm thermal / derating curves, the exact mechanical drawing, pin orientation and capacitor requirements.
Source maximum output-capacitance field: “Not limited in source; validation required”. No validated upper design limit is provided. Confirm inrush, startup, stability and protection before selecting capacitance.
Source MTBF statement: 2×10^6h. Prediction method, stress profile and supporting report are not supplied; this is unverified, not a lifetime or reliability guarantee.

*1: See enable control for *1 / *2, and parameter configuration for *3 / *4 / *5.

*2: See enable control for *1 / *2, and parameter configuration for *3 / *4 / *5.

*3: See enable control for *1 / *2, and parameter configuration for *3 / *4 / *5.

*4: See enable control for *1 / *2, and parameter configuration for *3 / *4 / *5.

*5: See enable control for *1 / *2, and parameter configuration for *3 / *4 / *5.

View currently reviewed model-specific typical plots →

Do not transfer another model's plots to this series. Request original documents and further details by email, not public file downloads.

Source pin-location and mechanical drawings

Unmodified drawings from this series’ 2025V2 documents, preserving dimensions, orientation and pin diameters. They apply only to the stated series. Confirm the current released drawing before design or ordering; these do not establish drop-in compatibility.

2828x-240x · 2025V2 · Pin-location drawing — 2828x-240x · 2025V2 · Original Chinese labels: 顶视 = top view; 底视 = bottom view. Follow the stated view and this series’ pin definitions.

2828x-240x · 2025V2 · Mechanical dimensions — 2828x-240x · 2025V2 · Original Chinese labels: 顶视 = top view; 底视 = bottom view. Follow the stated view and this series’ pin definitions.

From documented functions to model-level curves

Typical performance curves for this series

Extracted from supplied 2025V2 specification documents, reviewed on 2026-10-29. These are typical characteristics from those documents, not independent Jingmu measurements or guaranteed limits. Original plots without company identifiers are reproduced without redrawing data, axes or legends; documented conditions appear alongside each plot.

2828x-240x · 28 V / 240 W

1/8 brick · Rated input 18–36 V · Nominal output 28 V / 240 W

x is a series placeholder, not a complete order code. Plotted current ranges do not increase the nominal power rating or establish continuous full power across the full input/temperature range.

2828x-240x 28 V / 240 W Conversion efficiency, typical plot from 2025V2 documentation — 2828x-240x · 2025V2 · p3 typical characteristics
Horizontal axis: output current 1–9 A; vertical axis: efficiency. Input-voltage traces: Vin = 18 / 28 / 36 V. Temperature and cooling conditions are not stated.

2828x-240x 28 V / 240 W Output ripple waveform, typical plot from 2025V2 documentation — 2828x-240x · 2025V2 · p3 typical characteristics
Cin = 220 µF; Cout = 440 µF; voltage scale 100 mV/div; time scale 1 µs/div. Input voltage, load current, temperature, cooling, measurement bandwidth and probe method are not stated.

2828x-240x 28 V / 240 W Load-transient response, typical plot from 2025V2 documentation — 2828x-240x · 2025V2 · p3 typical characteristics
Cout = 440 µF; load steps 0 → 9 → 0 → 9 → 0 A; voltage scale 500 mV/div; time scale 4 ms/div. Input voltage, temperature, cooling, load slew rate and measurement bandwidth are not stated.

Compare series in the same family

2805x-200x · 5V / 200W 2809x-240x · 9V / 240W 2812x-240x · 12V / 240W 2815x-240x · 15V / 240W 2820x-240x · 20V / 240W 2824x-240x · 24V / 240W 282V5x-125x · 2.5V / 125W 2836x-240x · 36V / 240W 283V3x-165x · 3.3V / 165W 2848x-240x · 48V / 240W 287V5x-240x · 7.5V / 240W

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