DLP® Concepts to Mount Series 322 DMDs Updated: 28 July 2023

Important considerations for mounting the DMD
Important considerations when mounting the DMD include optical alignment, ensuring a good electrical connection, and control of the mounting loads (forces) applied to the DMD electrical and thermal areas. The DMD data sheet specifies the maximum loads for each of these areas. DMDs with pads require a continuous load on the DMD for a good electrical connection. The load applied to the DMD electrical area should be that which is needed to maintain a good electrical connection and general clamping to secure the DMD in place. Good mounting practices include: Use of the DMD defined Datums ‘A’, ‘B’, and ‘C’ for both optical and electrical alignment DMD must be pushed against the interface Datums ‘B’ and ‘C’ Control of part tolerances which contribute to changes in the loads applied to the DMD (gaps for springs, gaps between PCB and boss, etc…) Control part tolerances for features used to align the DMD, electrical interposer, and PCB A design that prevents interactions between loads applied to the thermal and electrical areas Preventing PCB from bending (clamp material and thickness) If additional loads are needed to secure the DMD they should be applied in a lateral direction to not apply additional loads to the DMD Control mechanical forces on the DMD thermal and electrical interface areas to prevent them from exceeding those specified in the DMD data sheet (System Mounting Interface Loads section). Mechanical forces should be uniformly applied (even clamping pressure) Partial tightening of fasteners, order of tightening fasteners, possible use of a fixture Design Method to control of forces (Best method) Forces controlled by design details rather than use of fastener torques or special procedures Minimize force variations from part tolerances by use of coil springs, flat springs, shoulder screws Minimum and maximum force range easily determined and controlled Assembly Process Method to control of forces Forces controlled by use of fastener torque and special procedures Greater variation and uncertainty of force applied than Design Method of control Applied forces highly dependent on assembly person and process Torque value determined for a specific design (based on materials and fasteners used) Difficult to determine clamping forces from fasteners These concepts can be modified to meet the specific requirements of the application and its environment. In so doing ensure the modifications allow the DMD specifications to still be met
Series 322 DMD Mounting Concepts
(Select Figures below or Mounting Concept Title for detailed information)
| Mounting Concept 8991 TI Drawing 2518991 Standard height interposer Mechanical loads on DMD thermal area are controlled by design (coil springs) Mechanical loads on DMD electrical area are controlled by design (coil springs) Mechanical loads on the thermal and electrical areas are controlled independent of each other Important: Selection of coil springs are critical for control of mounting loads
| Mounting Concept 8809 TI Drawing 2518809 Standard height interposer Mechanical loads on DMD thermal area are controlled by design (coil springs) Mechanical loads on DMD electrical area are controlled by design (coil springs) Mechanical loads on the thermal and electrical areas are controlled independent of each other Important: Selection of coil springs are critical for control of mounting loads
| Mounting Concept 8818 TI Drawing 2518818 Low height interposer Mechanical loads on DMD thermal area are controlled by design (coil springs) Mechanical loads on DMD electrical area are controlled by design (coil springs) Mechanical loads on the thermal and electrical areas are controlled independent of each other Important: Selection of coil springs are critical for control of mounting loads