Small Instrumentation Modules SIM928 — Rechargeable isolated voltage source · ±20 V isolated voltage source · Ultra-low noise output · Two switchable, recharging batteries for continuous operation · Battery lifetime: 1000 charge cycles · Output floats to ±40 V · Short-circuit protected SIM928 Isolated Voltage Source The SIM928 Isolated Voltage Source is ideal for applications where ultra-clean DC voltage is required. Voltage can be set between ±20 VDC with millivolt resolution, and the source can drive up to ±10 mA. The output circuit is optically isolated from all earth-referenced charging circuitry, providing maximum flexibility and noise immunity. The system can float to ±40 V, and the output is short-circuit protected. At the heart of the SIM928 are two independent nickel-metalhydride rechargeable batteries, each providing up to 12 hours of operation under full-load conditions. When a battery is nearly depleted, the SIM928 automatically switches in a second battery. The switchover between batteries is virtually glitch-free, giving you uninterrupted power around the clock. The depleted battery is automatically charged to capacity in about 5 hours. The batteries are guaranteed for 1000 charging cycles, and SRS offers replacement battery sets. Stanford Research Systems In applications that occur over long time intervals, starting with a fully charged battery may be desirable. A battery charge override feature allows you to manually switch in the fully charged battery (assuming it is in “ready” state) at any time. Banana binding posts are provided for the + terminal, – terminal and chassis ground.

Switchover glitch Battery charge override Output Output range ±20 V, 1 mV resolution Max. output current ±10 mA Floating output ±40 V (common mode to ground) Noise 10 µVrms (1 kHz bandwidth) Current limit 15 mA Short-circuit duration indefinite General Operating temperature 0 °C to 40 °C, non-condensing Interface Serial via SIM interface Connectors Banana binding posts (+ terminal, – terminal, and chassis ground) DB15 (male) SIM interface Power Powered by SIM900 Mainframe, or by user-provided DC power supply (+24 V, –15 V and +5 V) Dimensions 1.5" × 3.6" × 7.0" (WHD) Weight 3 lbs. Warranty One...