TMC - PEPS - Precision Electronic Positioning System - A Simplied Analog Version of Electro-Damp PLS

U.S. Patent No. 5,832,806
General Specifications
	Power Supply:
		100,120,230, 240VAC, or 15VDC (7 W nom. 12 W max.)
	Leveling Accuracy:
		5-10 micron (height, typ.)
		5-10 microradian (Pitch and roll, typ.)
	Leveling Hysteresis:
		<5 microns/microradians (integrators on, typ.) <50 microns/microradians (integrators off, typ.)
	Air Consumption:
		0.0375 scfm per psig of isolator pressure approx. (dry, clean air, filtered to 20 µm or better)
	Physical Dimensions:
		6.5" (h) x 4.1 25" (w) x 7.5" (d) (165mm (h) x 104 mm (w) x 190 mm (d))
	Weight (unit alone):
		5 Lb. (2.3 Kg)
	Proximity Sensors:
		M-30 NAMUR eddy-current sensors (15mm operating height)
User Interface Includes
	Controls:
		Height, pitch and roll gain controls. "Level OK" range adjustment "Range OK" and integrator status indication lamps. Simple Dip-switch control over damping and integration modes. Simple voltage selection for operation in most countries. Quick disconnects for all power, air, sensor, and I/O plugs
	DB-25 Connectors:
		Height, Pitch and roll analog outputs and feed-forward inputs. Open-collector "status OK" logic output. Optional external power supply inputs.
	System Includes:
		PEPS^® main control unit, proximity sensors,120VAC power cord. Flexible polyurethane tubing and fittings. Air pressure regulator/filter combination. Comprehensive operating manual. DB-25 male connector with shell. All required tools.

PEPS

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PEPS® (Precision Electronic Positioning System) is a non-contacting, analog height control system for TMC pneumatic vibration isolation systems. Such systems normally incorporate mechanical height valves and a mechanical height sensing linkage. Its applications range from semiconductor manufacturing equipment to improve settling time and increase yields, to precision laboratory environments which demand the optimum noise performance and platform stability.

TMC PEPSå installation

TMC’s active systems are ideal for
applications with motorized stages

Features

10 micron/micro-radian height and tilt stability and repeatability. With the switchable integrators on, this repeatability becomes completely independent of the platform’s loading or load distribution.
Non-contacting sensors improve the vibration isolation performance of the system (compared with conventional mechanical valves).
Improved damping over conventional mechanical valving systems (when used with TMC isolators).
Full analog feedforward inputs allows PEPS to make needed pressure corrections for payload shift before the platform can deflect, minimizing settling times. The result is higher throughputs for applications such as semiconductor inspection tools.
Feedforward inputs also allow simplified docking of stages in inspection machines and allow for electronic control of a platform’s alignment with other equipment or tables.
A true analog/proportional valving system eliminates "pulse noise" introduced on the payload by other PWM (pulse-width modulated) systems.
An adjustable logic output provides a “status OK” signal for wafer loaders or other position-sensitive applications.
“Smart” turn-on mode reduces “hunt and seek” of the platform when the system is “cold” started.
The controller provides fully buffered analog outputs indicating the platform’s height, pitch, and roll.
A compact package measuring only 6.5(h) x 4.125(w) x 7.25(d) inches (including power supply).
Simple design – there are only three gain controls to be set for normal operation. Controller modes are selected using a simple DIP switch, and all input/output functions are accessible through a single DB-25 connector. Once configured, it has a one-switch operation.
All controls and access are on one side of the package.
PEPS can be powered remotely for ease of integration into OEM applications.
Compatible with a variety of height sensors to meet different space requirements
Air flow is valved off when the unit is either switched off or unplugged, preventing isolator over-inflation.
A plumbed exhaust line for clean disposal of waste air.