Up to 100 Ap/195 Vp, DC to 100 kHz, Three-Phase


Industrial amplifier for pulse or continuous duty

  • Field-selectable controlled-voltage or controlled-current operation
  • Can be switched between rail supply modes to optimize for various load impedances
  • Protection circuits guard against over/under voltage, over current, over temperature, and circulating ground currents

Key Performance Capabilities:

  • Over 12,000 watts peak for 40 ms and 5,500 watts peak continuous into a 1-ohm load
  • 40 ms pulses of up to 105 amperes peak into a 1-ohm load.
  • Frequency bandwidth of DC to 50 kHz at rated power; DC to 100 kHz at reduced power
  • Continuous system output of 800 Vp or 170 Ap maximum are possible with multiple, interconnected amplifiers

The 7548 amplifier is a DC-enabled, high-powered unit designed to provide very low noise and fast slew rates. A single 7548 has an output capability of 100 amperes peak and 200 volts peak when driving typical MRI gradient coil loads. It can output a 40 ms pulse with up to 105 amperes peak current into a 1-ohm load. If more current is needed, up to four amplifiers can be combined in series or parallel and operate as a single system.

The 7548 can operate in either voltage or current mode and features robust output devices and a power range of over 3300 watts RMS. It can safely drive a wide range of resistive, inductive loads.

Typical use includes as a power source for EMC testing in applications that require both continuous AC or DC signals and significant short term (burst) signals. It can be combined in a three-phase system ideal for MIL-STD-704F (AC and 28V DC tests).


AC Output

Note: Testing performed into resistive loads as specified. Performance reported is typical into the specified load up to 20 kHz frequency levels. Performance may be affected when operating into highly reactive loads or above 20 kHz, reducing maximum voltage, current and power output.

*Testing not performed.



40mSec Pulse,
20% Duty Cycle
5 Min,
100% Duty Cycle
1 Hr,
100% Duty Cycle
5 Min,
100% Duty Cycle
1 Hr,
100% Duty Cycle
Volts Amps Volts Amps Volts Amps Volts Amps Volts Amps Watts
Open 200 0 200 0 200 0 141 0 141 0 0
16 195 12 195 12 195 12 138 8 138 8 1170
8 183 23 183 23 183 23 129 16 129 16 2104
4 165 41 165 41 165 41 117 29 117 29 3381
2 150 75 * * 86 43 * * 61 30 1848
1.5 134 90 * * * * * * * * *
1 116 105 * * * * * * * * *
0.5 66 112 * * * * * * * * *

DC Output

7548 DC Power Output
7548 DC Thermal Testing


Frequency Data

7548 Frequency Response
7548 Voltage Potential
7548 Output Impedance

Front & Back

7548 Front Panel


7548 Back Panel



Note: Testing performed at 208V/415V AC. 7548amplifiers can operate from 400V AC ±10%. Since these amplifiers have an unregulated power supply, low line conditions may slightly affect the maximum voltage potential. All testing was performed in Controlled-Voltage (CV) mode. Accuracy was measured when driven into a 10-ohm load with between 0.1V DC and 6V DC or between 0.2V AC and 5V AC presented at its inputs.

Frequency Response, DC - 30 kHz (1 watt): +0.1 to -0.5 dB
8-Ohm Power Response (continuous duty):
   DC to 40 kHz: ± 180 Vpk
   DC to 50 kHz: ± 150 Vpk
   DC to 150 kHz: ± 50 Vpk
   DC to 200 kHz: ± 25 Vpk
Maximum Continuous Output Power: 3300 watts RMS
Power Sinking: 1.2 kVA at 120 VAC
Slew Rate: >35 V/µs
Residual Noise, 10 Hz - 20 kHz: Less than 250 µV
Unit to Unit Phase Error: ±0.1 degrees at 60 Hz
Phase Response (10 Hz - 10 kHz) : ±5 degrees plus 600 nsec propogation delay
THD (DC - 20 kHz): Less than 0.25%
Output Offset: Less than ±200 µV
Output Offset Current: Less than 10 mA, DC
DC Drift,
   From Cold to Maximum Operating Temperature:
   After 20 minutes of Operation: ±200µV
Output Impedance: 3.2 mOhm in Series with 2.2 µH
Input Characteristics,
   Balanced with ground:
Three terminal barrier block connector, 20k ohm differential
   Unbalanced: BNC connector, 10k ohm single ended.
Gain, Voltage Mode: 20 volts/volt;  Current Mode: 20 amperes/volt
Gain Linearity (over input signal, from 0.2V to 5V),
   DC: 0.0125%
   AC: 0.030%
Max Input Voltage: ±10V, balanced or unbalanced
Input Impedance: 20 kOhm; differential
Input Sensitivity: 3.0V input for 3800W output into 1 ohm (adjustable)
Common Mode Rejection Range: -±11 VDC maximum
Common Mode Rejection Ratio: Better than -65 dB

Status Display, Control, I/O

Front Panel LED Displays indicate: Ready, Standby, Fault
Soft Touch Switches for: Run, Stop, Reset
LCD Display: Can be configured for up to four simultaneous displays reporting one, two, or all four of the following: Vp, VRMS, Ap, ARMS Also reports any fault conditions that occur and suggests corrective action.
Back Panel Power Connection: NEMA-style locking receptacle; matching AC connector also included
Signal Output:4-position terminal barrier block (OUTPUT / COMMON / SAMPLED COMMON / CHASSIS GROUND); resistor installed between SAMPLED COMMON AND CHASSIS GROUND is a 2.7-ohm, 2W, 5%, metal-oxide resistor
Signal Input: User-selectable BNC or Barrier Strip, balanced or unbalanced
Interlock Connector: 25-pin D-sub connector used for amplifier control and status applications; also used in multi-amplifier applications

Communication Capabilities

Current Monitor: 20A/V ±1%; 10A/V ±1% (differential configuration)
Reporting: System Fault, Over Temp, Over Voltage, Over Load
Remote Control via Interlock Connector: Force to Standby, Reset after a fault


Over/Under Voltage:
±10% from specified supply voltage amplifier is forced to Standby
Over Current:
Breaker protection on both main power and low voltage supplies
Over Temperature:
Separate output transistor, heat sink, and transformer temperature monitoring and protection

Physical Characteristics

The amplifier is designed for stand-alone or rack-mounted operation. The chassis is aluminum with a black powder-coat finish. The unit occupies five EIA 19-inch-wide units.
Weight: 103 lbs (46.7 kg), Shipping 115 lbs (52.2 kg)
AC Power: Three-phase, 208 VAC (±10%), 47-60 Hz, 20A AC service; (400 VAC (±10%), 15A model available)
Operating Temperature:
10°C to 50°C (50°F to 122°F), maximum output Power de-rated above 30°C (86°F).
Humidity: 70% or less, non-condensing
Cooling: Forced air cooling from front to back through removable filters via four 100-ft3/min. fans. No space is required between rack-mounted amplifiers. Air filters are removeable from the rear via one fastener per side and may be eliminated if cabinet filtration is provided.
Dimensions: 19" x 22.8" x 8.75" (48.3 cm x 57.9 cm x 22.2 cm)

400V versions of this product bear the CE mark


7548 Datasheet

Complete technical specifications

7548/7794/7796/7796HC Operator's Manual

For 7548, 7794, 7796 and 7796HC amplifiers

Multiamp Configuration Guide

For 7224, 7226, 7548, 7794, 7796 and 7796HC amplifiers

SIM Pinouts and Functions

For 7224, 7226, 7548, 7794, 7796 and 7796HC amplifiers

DXF Model for Chassis

For 7548 amplifiers

STEP file for Chassis

For 7548 amplifiers

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Ground Current Limiter

Active protection with red LED indicator; resettable




Voltage & Current Monitor

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