ICL7137 Intersil Corporation, ICL7137 Datasheet

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... The ICL7136 is designed to interface with a liquid crystal dis- play (LCD) and includes a multiplexed backplane drive; the ICL7137 will directly drive an instrument size, light emitting diode (LED) display. The ICL7136 and ICL7137 bring together a combination of high accuracy, versatility, and true economy ...

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... Analog Input Voltage (Either Input) (Note 1 Reference Input Voltage (Either Input Clock Input ICL7136 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TEST to V+ ICL7137 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . GND to V+ Operating Conditions Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . . .0 CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the device at these or any other conditions above those indicated in the operational sections of this specifi ...

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... FIGURE 1. ICL7136 TEST CIRCUIT AND TYPICAL APPLICATION WITH LCD DISPLAY COMPONENTS SELECTED FOR 200mV FULL SCALE + FIGURE 2. ICL7137 TEST CIRCUIT AND TYPICAL APPLICATION WITH LED DISPLAY COMPONENTS SELECTED FOR 200mV FULL SCALE ICL7136, ICL7137 TEST CONDITIONS V+ = 5V, Segment Voltage = ...

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... Digital supply is generated internally 4.5V TEST • ICL7136 DISPLAY: LCD Type: Direct drive with digital logic supply amplitude. • ICL7137 POWER SUPPLY: DUAL 5. +5V to GND V- = -5V to GND Digital Logic and LED driver supply V+ to GND (Typ • ICL7137 DISPLAY: LED Type: Non-Multiplexed Common Anode ...

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... OSC3 39 6 OSC2 40 7 OSC1 ICL7136, ICL7137 FUNCTION Supply Power Supply. Output Driver Pin for Segment “D” of the display units digit. Output Driver Pin for Segment “C” of the display units digit. Output Driver Pin for Segment “B” of the display units digit. ...

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... Detailed Description Analog Section Figure 3 shows the Analog Section for the ICL7136 and ICL7137. Each measurement cycle is divided into four phases. They are (1) auto-zero (A-Z), (2) signal integrate (INT) and (3) de-integrate (DE), (4) zero integrate (ZI). Auto-Zero Phase During auto-zero three things happen. First, input high and low are disconnected from the pins and internally shorted to analog COMMON ...

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... The limitations of the on chip reference should also be recognized, however. With the ICL7137, the internal heating which results from the LED drivers can cause some degradation in performance. Due to their higher thermal resis- tance, plastic parts are poorer in this respect than ceramic. ...

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... ON. In all cases negligible DC voltage exists across the segments. TO LCD DECIMAL Figure 8 is the Digital Section of the ICL7137 identical POINTS to the ICL7136 except that the regulated supply and back plane drive have been eliminated and the segment drive has been increased from 2mA to 8mA, typical for instrument size common anode LED displays ...

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... FOR CLARITY OSC 1 System Timing Figure 9 shows the clocking arrangement used in the ICL7136 and ICL7137. Two basic clocking arrangements can be used: 1. Figure 9A, an external oscillator connected to pin 40. 2. Figure 9B, an R-C oscillator using all three pins. The oscillator frequency is divided by four before it clocks the decade counters ...

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... The integrating capacitor should be selected to give the maximum voltage swing that ensures tolerance buildup will not saturate the integrator swing (approximately 0.3V from either supply). In the ICL7136 or the ICL7137, when the analog COMMON is used as a reference, a nominal +2V full- scale integrator swing is fine. For the ICL7137 with +5V supplies and analog COMMON tied to supply ground ...

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... Typical Applications The ICL7136 and ICL7137 may be used in a wide variety of configurations. The circuits which follow show some of the possibilities, and serve to illustrate the exceptional versatility of these A/D converters. The following application notes contain very useful information on understanding and applying this part and are available from Intersil semiconductor ...

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... If COMMON is not shorted to GND, the input voltage may float with respect to the power supply and COMMON acts as a pre-regulator for the reference. If COMMON is shorted to GND, the input is single ended (referred to supply GND) and the pre-regulator is overridden. FIGURE 13. ICL7137 WITH AN EXTERNAL BAND-GAP REFERENCE (1.2V TYPE) TO PIN 1 OSC 1 ...

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... BUFF 28 INT 27 0.047 DISPLAY GND 21 The resistor values within the bridge are determined by the desired sensitivity. FIGURE 17. ICL7137 MEASURING RATIOMETRIC VALUES OF QUAD LOAD CELL LOGIC ...

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... DISPLAY BACKPLANE Test is used as a common-mode reference level to ensure compatibility with most op amps. ICL7136, ICL7137 10 F SCALE FACTOR ADJUST (V = 100mV FOR AC TO RMS) REF 220k 470k 1 F 10k 4. 100pF (FOR OPTIMUM - BANDWIDTH) FIGURE 21 ...

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... POL (20) BP/GND (21) G (22 (23 (24 (25 (26) (27) INT ICL7136, ICL7137 PASSIVATION: Type: PSG Nitride Thickness: 15k WORST CASE CURRENT DENSITY A/cm ICL7136, ICL7137 (13) (12) (11) (10) (9) (8) (7) (6) (28) (29) (30) ...

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... B1 maximum dimensions do not include dambar protrusions. Dambar protrusions shall not exceed 0.010 inch (0.25mm the maximum number of terminal positions. 10. Corner leads (1, N, N/2 and N for E8.3, E16.3, E18.3, E28.3, E42.6 will have a B1 dimension of 0.030 - 0.045 inch (0.76 - 1.14mm). ICL7136, ICL7137 E40.6 40 LEAD DUAL-IN-LINE PLASTIC PACKAGE SYMBOL A ...

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... However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see web site http://www.intersil.com ICL7136, ICL7137 Q44.10x10 44 LEAD METRIC PLASTIC QUAD FLATPACK PACKAGE ...