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HT7500 Clinical Thermometer

· Bonding option for Centigrade / Fahrenheit measure-

HT7500 Clinical Thermometer
Features
· Single-chip CMOS construction · Single 1.5V battery operation · Measurement range: +32.0~+42.0°C · Alarm warning for fever · Highest temperature hold · Auto power off after 8 min 40 sec · One-key input switch for ON / OFF · Displays last time measured temperature
· Bonding option for Centigrade / Fahrenheit measure-
General Description
The HT7500 is a CMOS digital clinical thermometer IC for measuring body temperature in Centigrade (°C) or Fahrenheit (°F) mode by its bonding option. It also provides alarm and auto power off functions. The other electronic components are LCD display, thermister, 1.5V battery, ON / OFF switch, buzzer, resistors and capacitors.
Block Diagram
Rev. 1.20
September 4, 2007
HT7500
Pad Assignment
The IC substrate should be connected to VDD in the PCB layout artwork.
Pad Coordinates
Pin No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 X -929.875 -885.969 -885.970 -885.970 -885.970 -929.549 -929.635 -868.914 -769.896 -670.794 -571.776 -245.230 -63.255 104.027 371.023 859.556 936.575 Y 234.628 70.023 -46.627 -242.787 -347.652 -503.467 -617.438 -858.957 -858.957 -858.957 -858.957 -858.919 -858.919 -858.982 -858.982 -827.747 -119.962 Pin No. 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 X 936.575 936.575 936.575 936.575 936.575 936.575 936.575 671.959 568.970 469.260 368.401 92.064 -19.960 -226.930 -366.670 -646.030 Y
Unit: mm
Rev. 1.20
September 4, 2007
HT7500
Pad Description
Absolute Maximum Ratings
Supply voltage........................0V to 2.0V Input voltage ...............VSS-0.5V to VDD+0.5V Operation Temperature............-2.0°C to +75°C Storage Temperature .............-55°C to +125°C
Rev. 1.20
September 4, 2007
HT7500
Electrical Characteristics
LCD Electrode Pattern
SA1 COM1 COM2 COM3 F1 E1 H1
SA2 A1 G1 D1
SB2 A2 G2 D2
SB3 B2 C2 H2
SC2 A3 G3 D3
SC3 B3 C3 H3
SD1 A4 B4 C4
Note: 1 / 3 duty, 1 / 2 bias (LCD uses 3V)
Function Description
· Power sw: push switch to power on or power off. · When power on: push the switch, then it will generate
· j. It will automatically turn the power off when
measurement is over for 8 min 40 secretary.
Rev. 1.20
September 4, 2007
HT7500
k. When measurement is over, but if the temperature rises within 8 min 40 sec, the °C (or °F) mark will flash again (repeat from step 2-d), and starts to count 8 min 40 sec again. l. When beep sound is on for 4 sec, the temperature is not measured.
Flow Chart
Rev. 1.20
September 4, 2007
HT7500
Application Circuits
Rev. 1.20
September 4, 2007
HT7500
Holtek Semiconductor Inc. (Headquarters) No.3, Creation Rd. II, Science Park, Hsinchu, Taiwan Tel: 886-3-563-1999 Fax: 886-3-563-1189 http://www.holtek.com.tw Holtek Semiconductor Inc. (Taipei Sales Office) 4F-2, No. 3-2, YuanQu St., Nankang Software Park, Taipei 115, Taiwan Tel: 886-2-2655-7070 Fax: 886-2-2655-7373 Fax: 886-2-2655-7383 (International sales hotline) Holtek Semiconductor Inc. (Shanghai Sales Office) 7th Floor, Building 2, No.889, Yi Shan Rd., Shanghai, China 200233 Tel: 86-21-6485-5560 Fax: 86-21-6485-0313 http://www.holtek.com.cn Holtek Semiconductor Inc. (Shenzhen Sales Office) 5 / F, Unit A, Productivity Building, Cross of Science M 3rd Road and Gaoxin M 2nd Road, Science Park, Nanshan District, Shenzhen, China 518057 Tel: 86-755-8616-9908, 86-755-8616-9308 Fax: 86-755-8616-9722 Holtek Semiconductor Inc. (Beijing Sales Office) Suite 1721, Jinyu Tower, A129 West Xuan Wu Men Street, Xicheng District, Beijing, China 100031 Tel: 86-10-6641-0030, 86-10-6641-7751, 86-10-6641-7752 Fax: 86-10-6641-0125 Holtek Semiconductor Inc. (Chengdu Sales Office) 709, Building 3, Champagne Plaza, No.97 Dongda Street, Chengdu, Sichuan, China 610016 Tel: 86-28-6653-6590 Fax: 86-28-6653-6591 Holtek Semiconductor (USA), Inc. (North America Sales Office) 46729 Fremont Blvd., Fremont, CA 94538 Tel: 1-510-252-9880 Fax: 1-510-252-9885 http://www.holtek.com
Rev. 1.20
September 4, 2007