Document
NJU9214
PRELIMINARY 4•3/4 DIGIT SINGLE CHIP DIGITAL MULTIMETER LSI
! GENERAL DESCRIPTION
The NJU9214 is a 4•3/4 digits single chip digital multimeter LSI with 42 segments bargraph display. The NJU9214 realizes high precision of ±40,000 counts measurement by the NJRC original dual-slope A to D converter and realizes also quick response bargragh display and auto-ranging by another high speed dual-slope A to D converter. The input attenuator part is simplified because the resistor for resistance measurement is applied for voltage bleeder resistor. Furthermore, the NJU9214 realizes root-mean-square measurement for AC voltage and current by connecting a External RMS-DC Converter, and Data output by the on chip RS-232C interface circuit. The NJU9214 is suitable for high precision and high performance multimeter.
PACKAGE OUTLINE
NJU9214FG1
! FEATURES
• 4•3/4 Digit Display (Available for UP to ±39,999 Display) • 42 Segments Quick Response Bargraph Display • NJRC Original Dual-Slope A to D Converter (±40,000Counts) • High Speed Dual-Slope A to D Converter (±400Counts) • Quick Response Auto-Ranging (20times/sec) • Frequency/Capacitance/Tachometer/Adapter Measurement • Root-Mean-Square Measurement by connecting a External RMS-DC Converter • External Relay Driving • Data Memory/Data Hold/Relative Display/MAX, MIN Display • Power-on Initializing • Auto Power-off • Buttery Life Detector • Rotary/Push SW Mode Selection • 1/4 Duty LCD Display Driver • Piezo Buzzer Direct Driving • RS-232C Interface • External Reference Input required • Low Operating Current • C-MOS Technology • Package Outline TQFP100
NJU9214
!BLOCK DIAGRAM
REGURATOR
REFERENCE
VREF1
VREF2
RESISTORS and SWITCHS
VDDA AGND VSSA +5.0V 0V -5.0V IVSL, IVSL, IVSH VI, , VI VR2 to 7, OVH, OVH, OVX ADP SGND
VDDD VSSD 0V 5.0V
VREF3
A
EXTERNAL
SWITCH NETWORK
DCV, DCV, ACV, ACV, Ω, , ,CAP ,CAP, CAP, DCmA, DCmA, ACmA, ACmA, FRQ, FRQ, rpm
REFERENCE BUFFER
BATT LOW DETECTOR
FRQ
ANALOG SECTION
COM
HIGH SPEED A/D SECTION
HIGH RESOLUTION A/D SECTION
CAPACITOR A/D SECTION
BUFFER
CONVERTER
RMS-DC
RMSIN
SWITCH NETWORK I/F
HIGH SPEED A/D I/F
HIGH RESOLUTION A/D I/F
RD1 to 4
RELAY CONTROLER
SWITCH NETWORK CONTROLER
HIGH SPEED A/D CONTROLER
HIGH RESOLUTION A/D CONTROLER
POWER ON INITIALIZE
DIGITAL SECTION
4bitBUS FC1 to 4, KI1 to 5
KEY
CONTROLE
RS232C
CONTROLER
BUZZER
CONTROLER
4bit CPU
LCD CONTROLER
LCD DRIVER and
TXD DTR DSR
TRX TXS RST PON KEY MATRIX
TEST
OSC
POWER
BZ BUZZER
COM1 to 4
SEG1 to 28
T1 to T3
XT1
XT2
RS232C DRIVER
LCD
NJU9214
! PIN CONFIGURATION
VSSA SLEEP SEG28 SEG27 SEG26 SEG25 SEG24 SEG23 SEG22 SEG21 SEG20 SEG19 SEG18 SEG17 VSSD VDSP CIF2 CIF1 DTR DSR TXD
65
BLD
XT1
BUF CL2 CH2 VREF3 VREF2 VREF1 CH1 CL1 INT1 INT2 SGND2 SGND1 AGND IVSH IVSL ADP OVX OVH VR7 VR6 VR5 VR4 VR3 VR2 V1
75
70
XT2 BZ
60
55
50
SEG16 SEG15 SEG14 SEG13
80 45
SEG12 SEG11 SEG10 SEG9 SEG8
85 40
NJU9214FG1
90 35
SEG7 SEG6 SEG5 SEG4 SEG3 SEG2 SEG1 COM4 COM3 CMO2 COM1 T3 T2 T1 RST PON
95 30
100 1
5
10
15
20
25
ACOUT
RMSIN
VDDD
VDDA
RD1 RD2
RD3 RD4
RC0 RC1
RC2
RC3 FC1 FC2
TRX
FC4 KI1
KI2 KI3 KI4
RMS
TXS
KMS
! TERMINAL DESCRIPTION
No. 1 2 3 4 5 to 8 9 10 11 12 13 to 20 17 to 20 21 to 25 SYMBOL AC OUT VD D A RMSIN VD D D RD 1 to RD 4 TXS TRX KMS RMS RC 0 to RC 3 FC 1 to FC 4 KI1 to KI5 I/O Out In Out In In In In In I/O In FUNC TION Attenuator output termi nal (used at AC A, AC mA, FRQ, rpm) Analog VD D (VD D A = 5.0 ± 0.25V) RMS-Voltage Input T ermi nal D i gi tal VD D (VD D D = 5.0 ± 0.25V) Relay D ri vi ng T ermi nal RS232C Output-Rate Select T ermi nal L ; 9600bps H ; 2400bps RS232C Functi on Select T ermi nal Key Mode Select T ermi nal Range C ontrol Mode Select T ermi nal Range Select T ermi nal wi th Input Pull-up Resi stance (300kΩ) Functi on Select T ermi nal wi th Input Pull-up Resi stance (300kΩ) Opti onal Functi on C ontrol T ermi nal wi th Input Pull-up Resi stance (300kΩ)
FC3
KI5
NJU9214
No. 26 27 28 to 30 SYMBOL PON RST T1 to T3 I/O In In In Out Out In Out Out Out Out In I/0 Out In I/0 Out I/0 F UNC TION Auto Power-off Mode Release Terminal with Input Pull-up Resistance (300Ωk) System Reset Terminal with Input Pull-up Resistance(10kΩ) Test Terminal with Input Pull-up Resistance (300kΩ) LCD Common Terminal LCD Segment Terminal RS232C Data Set Ready Terminal RS232C Data-Terminal Terminal RS232C Data Output Terminal Piezo Buzzer Driving Terminal Crystal oscillation Inverter (Output) Crystal oscillation Inverter (Input) LCD driving voltage I/O Terminal Opened : VDSP=(VDDD-VSSD) X 3/5 Connected to VSSD : VDSP=(VDDD-VSSD) Digital VSS VSSD=0V Auto Power-off signal Terminal (Power-off:"H" Level) Analog VSS VSSA=-5.0V Buttery Life Detector Terminal, Detection: BLD<4.0V High-speed integration capacitor connecting Terminal High-speed integrator buffer output Terminal High-speed integrator reference capacitor connecting Terminal VREF1:High-accurate integrator reference voltage input Terminal VREF2:High-.