SPICE MODEL of NJM2374A in SPICE PARK. English Version is http://www.spicepark.net. Japanese Version is http://www.spicepark.com by Bee Technologies.

1. Device Modeling Report
COMPONENTS: PWM DC/DC CONVERTER IC
PART NUMBER: NJM2374A
MANUFACTURER: NEW JAPAN RADIO
Bee Technologies Inc.
All Rights Reserved Copyright (c) Bee Technologies Inc. 2006

2. PWM comparator diagram (High Voltage Detect)
Circuit Simulation Result
Reference
Voltage
VIN+
V(U1:IN+) V(X_U1.REF)
Oscillator
WaveformE L > >
S
V(U1:CT)
X_U1.LT
FF Reset
Collector-Emitter
Voltage
VC(X_U1.Q_QC)- VE(X_U1.Q_QC)
Time
Evaluation circuit
Rsc 0.22 L1
V+
180uH
RC
180 U1 D1
Vcc CD CS
VOUT
SI ES
5Vdc V+ CT DCON
IN+ GND 1
8.2k R2 NJM2374A CT RL
1500p 250
R1 Cout
953 150u
IC = 11
0
All Rights Reserved Copyright (c) Bee Technologies Inc. 2006

3. PWM comparator diagram (Current-Limit Active Point)
Circuit Simulation Result
Reference
Voltage
VIN+ Current-Limit
Active Point
V(U1:IN+) V(X_U1.REF)
Oscillator
Waveform
V(U1:CT)
FF Reset
X_U1.LT 1
Collector-Emitter
X_U1.FFS 1
Voltage
SEL>>
Time
Evaluation circuit
Rsc L1
V+
180uH
0.22 RC
180 U2 D1
Vcc CD CS
VOUT
SI ES
5Vdc V+ CT DCON VIL
IN+ GND 1 0
E1
8.2k R2 NJM2374A CT CTL
1500p OUT+ IN+
R1 Cout OUT- IN- T1 = 0
953 150u EVALUE
IC = 11 V(L1)*(V(CTL)-1) T2 = 5m V2
L1 R4
T3 = 5.05m
RLST 1MEG
0 T4 = 5.09m
250
V1 = 1
V2 = 1
0 V3 = 0.05
V4 = 1
All Rights Reserved Copyright (c) Bee Technologies Inc. 2006

4. Saturation Voltage 1 vs. collector Current
Circuit Simulation Result
2.0V
1.5V
1.0V
0.5V
0V
0A 0.5A 1.0A 1.5A 2.0A
V(Q2:c)
I(VIC)
Evaluation circuit
VIC
Q1
QC
Q2
QSW 14*I(VB)
VB R1 GVALUE
160
OUT- IN-
OUT+ IN+
GVC
I1
0.05Adc
0 0 0
*REMARK: Simulation use transistor inside .subckt model of NJM2374A
All Rights Reserved Copyright (c) Bee Technologies Inc. 2006

5. Saturation Voltage 2 vs. collector Current
Circuit Simulation Result
2.0V
1.5V
1.0V
0.5V
0V
0A 0.5A 1.0A 1.5A 2.0A
V(Q1:c)
IC(Q1)
Evaluation circuit
Q1
QC 14*I(VB)
GVALUE
VB
OUT- IN-
OUT+ IN+
GVC
I1
0.05Adc
0 0
0
*REMARK: Simulation use transistor inside .subckt model of NJM2374A
All Rights Reserved Copyright (c) Bee Technologies Inc. 2006

6. Step-Down Converter Reference
Circuit Simulation Result
15V 30V
1 2
VIN=25V
10V 20V
VOUT=5V
5V 10V
>>
0V 0V
0s 0.5ms 1.5ms 2.5ms 3.5ms 4.5ms
1 V(VOUT) 2 V(Vcc:+)
Time
Evaluation circuit
Rsc
V+
U1
0.22 CD CS L1
SI ES
VOUT
Vcc CIN V+ CT 1
IN+ GND 220uH
25Vdc 100uF RL
3.6k R2 NJM2374A CT 10
470p D1 Cout
R1 DCON 470u
1.2k
0
0
All Rights Reserved Copyright (c) Bee Technologies Inc. 2006

7. Step-Up Converter Reference
Circuit Simulation Result
15.0V
VOUT=12V
12.5V
10.0V
7.5V
VIN=5V
5.0V
2.5V
0V
0s 2ms 4ms 6ms 8ms 10ms
V(VOUT) V(Vcc:+)
Time
Evaluation circuit
Rsc 0.22 L1
V+
180uH
RC
180 U1 D1
Vcc CD CS
VOUT
SI ES
5Vdc V+ CT DCON
IN+ GND 1
8.2k R2 NJM2374A CT RL
1500p 250
R1 Cout
953 150u
IC = 11
0
All Rights Reserved Copyright (c) Bee Technologies Inc. 2006

8. Inverting Converter Reference
Circuit Simulation Result
1 -12V 2 12V
-10V 10V
VOUT=-12V
-8V 8V
VIN=5V
-6V 6V
-4V 4V
-2V 2V
>>
0V 0V
0s 10ms 20ms 30ms 40ms 50ms
1 V(OUT) 2 V(Vcc:+)
Time
Evaluation circuit
Rsc
U1
0.22 CD CS D1
SI ES OUT
Vcc CIN V+ CT 1
IN+ GND DCON
5Vdc 100uF L1
953 R2 NJM2374A CT 90uH Cout RL
1300p 250
R1 1 1000uF
8.2k
IC = 11.5
0
All Rights Reserved Copyright (c) Bee Technologies Inc. 2006