The JTMA7138 is a single-phase, constant-on-time, and synchr(2)

五,产品封装图 (Package)

六.电路原理图

七,功能概述
Power Good Indicator
The JTMA7138 features an open-drain PGOOD output pin to indicate one of the IC’s working statuses including
soft-start, under-voltage fault, over-current fault, and over-voltage faule. The unique fault-identification capability can
drastically reduce trouble-shooting time and effort.
The pull-down resistance of the PGOOD pin correspondsto the fault status of the controller. During soft-start or if
an under voltage fault occurs, the PGOOD pull-down re-sistance is 95Ω, or 32Ω for an over current fault, or 63Ω
for an over voltage fault. The pull-low resistance is unde-fined if VCC is below the rising/falling POR threshold.
Over-Temperature Protection (OTP)
When the junction temperature increases above the ris-ing threshold temperature TOTR, the IC will enter the
over-temperature protection (OTP) state that suspends the PWM, which forces the LG and UG gate drivers to
output low voltages. The status of the PGOOD pin does not change, nor does the converter latch-off. The thermal
sensor allows the converters to start a start-up process and regulate the output voltage again after the junction
temperature cools by 25oC. The OTP is designed with a 25oC hysteresis to lower the average TJ during continu-
ous thermal overload conditions, which increases life- time of the JTMA7138.
Over-Current Protection (OCP) and Short-Circuit Pro-tection (SCP)
The over-current protection (OCP) is designed to resist the slow slew rate load current; on the other hand, the
short-circuit protection (SCP) is used to take care of rapid shorted output. The setpoint for OCP and SCP is pro-
grammed with resistor RSEN that is connected across the ISEN pin and drain of the low-side MOSFET. The SCP
setpoint is internally set to twice the OCP setpoint.
The inductor current develops a negative voltage across the RDS(ON) of the low-side MOSFET that is sampled and
held shortly before LG gate-driver output goes low. The OCP fault occurs if ISEN rises above the OCP threshold
current IOC (typical :26µA) while attempting to null the nega-tive voltage across the PHASE and GND pins. When the
ISEN exceeds IOC, the OCP counter starts to work.
Meanwhile, pulses on all the PWM (ISEN > IOC) remains for 20µs, the OCP will be triggered. When ISEN falls below IOC
on a PWM pulses before 20µs has elapsed, the counter will be reset. The SCP fault will occur within 10µs when
I SEN exceeds twice I OC. The relationship between the sampled current and MOSFET current is given by:
ISEN × RSEN = RDS ( ON ) × IL
Which means the current sensing pin will source current to make the voltage drop on the MOSFET and is equal to
the voltage generated on the sensing resistor along the ISEN pin current flowing path.
八,相关产品

Part_No	Package & Pins	Topology	Architecture	Phase	No. of PWM Outputs	Output Current (max)(A)	Input Voltage (V)		Reference Voltage(V)	Bias Voltage (typ) (V)	Quiescent Current (typ)(uA)
Part_No	Package & Pins	Topology	Architecture	Phase	No. of PWM Outputs	Output Current (max)(A)	min	max	Reference Voltage(V)	Bias Voltage (typ) (V)	Quiescent Current (typ)(uA)
JTMA7068	SOP-14	Buck	VM	1	1	30	2.9	13.2	0.9	12	8000
	QSOP-16
	QFN4x4-16
JTMA7065	SOP-8	Buck	VM	1	1	20	2.9	13.2	0.8	12	5000
JTMA7065C	SOP-8	Buck	VM	1	1	20	2.9	13.2	0.8	12	5000
JTMA7098	QFN4x4-24	Multiphase	VM	2	1	60	3.1	13.2	0.6	12	5000
JTMA7120	SOP-8	Buck	VM	1	1	20	2.2	13.2	0.8	5月12日	2100
JTMA7120A	SOP-8	Buck	VM	1	1	20	2.2	13.2	0.8	5月12日	2100
JTMA7037/A/B	SOP-8	Buck	VM	1	1	5	5	13.2	1.25 / 0.8	5月12日	3000
JTMA7037/A/B	TSSOP-8	Buck	VM	1	1	5	5	13.2	1.25 / 0.8	5月12日	3000
JTMA7057	SOP-8	Buck	VM	1	1	10	3.3	5.5	0.8	5	2100
JTMA7062B	SOP-14	Buck	VM	1	1	10	5	13.2	0.8	12	2000
JTMA7066	TSSOP-24	Buck	VM	1	2	20	5	13.2	0.6	5月12日	4000
JTMA7066	QFN5x5-32	Buck	VM	1	2	20	5	13.2	0.6	5月12日	4000
JTMA7067N	SOP-14	Buck	VM	1	1	30	2.9	13.2	0.9	12	4000
	QSOP-16
	QFN-16
JTMA7073	SOP-14	Buck	VM	1	1	30	2.2	13.2	0.6	12	5000
JTMA7073A	SOP-14	Buck	VM	1	1	30	2.2	13.2	0.6	12	5000
JTMA7074	SOP-14	Buck	VM	1	1	25	2.2	13.2	0.8	12	5000
JTMA7095/A	LQFP7x7-48	Buck	VM	1	6	0.015	1.4	6.5	-	5	1800
	TQFN7x7-48	Boost
		Flyback
JTMA7116	TSSOP-24P	Buck	VM	1	2	20	2.97	5.5	0.8	5月12日	5000
JTMA7063	SOP-14	Buck	VM	1	1	10	5	13.2	0.8	12	3000
JTMA7064	SOP-8-P	Buck	VM	1	1	30	2.9	13.2	1.2	12	3000
JTMA7064	DIP-8	Buck	VM	1	1	30	2.9	13.2	1.2	12	3000
JTMA7108	SSOP-28	Buck	VM	1	2	20	5	24	0.9	5	1200
JTMA7108	QFN4x4-24	Buck	VM	1	2	20	5	24	0.9	5	1200
JTMA7158	SOP-20	Buck	VM	1	2	20	2.2	13.2	0.6	5月12日	4000
JTMA7181	SOP-8		VM	1	2	-	-	-	-	5月12日	550
JTMA7181	DFN3x3-10		VM	1	2	-	-	-	-	5月12日	550
JTMA38HC/42/3/4/5A	DIP-8	Buck	VM	1	1	1	1.2	9	24	5	9 ~ 24
	SOP-8	Boost
		Flyback
		Forward
JTMA7138	SSOP-16	Buck	VM	1	1	25	3	25	0.6	5	1700
	QFN4x4-16
	TQFN3x3-16
JTMA7199	TDFN3x3-10	Buck	COT	1	1	25	3	25	0.5	5	350
JTMA8700	QFN4x4-24	Buck	CM	2	1	40	4.5	13.2	0.6	5月12日	4000
JTMA8720B	SOP8-P	Buck	VM	1	1	20	3	13.2	0.8	5月12日	2500
JTMA8720B	TDFN3x3-10	Buck	VM	1	1	20	3	13.2	0.8	5月12日	2500
JTMA8722A/B/C/D	SOP8-P	Buck	VM	1	1	25	3	13.2	0.6 /0.8	5月12日	1200
JTMA8723	TDFN3x3-10	Buck	VM	1	1	25	4	13.2	0.8	5月12日	2000
JTMA8724	TDFN3x3-10	Buck	COT	1	1	25	4.5	25	0.6	5月12日	80
JTMA8725/A	SOP-8P	Buck	VM	1	1	25	4.5	13.2	0.8	5月12日	16000
JTMA8726	TQFN3x3-10	Buck	VM	1	1	25	4.5	13.2	0.6	5月12日	2500
JTMA8727/L	TDFN3x3-10	Buck	COT	1	1	30	3	25	0.8	5月12日	2000
JTMA8728	TQFN3x3-16	Buck	COT	1	1	30	1.8	28	0.6	5	600
JTMA8732	QFN4x4-24	Buck	VM	2	1	50	4.5	13.2	0.6	5月12日	5000
JTMA8811	TQFN4x4-24	Buck	COT	1	2	15	6	25	2	N	550
JTMA8812	TQFN4x4-24	Buck	COT	1	2	15	6	25	2	N	550
JTMA8813/A	TQFN4x4-24	Buck	COT	1	2	20	3	28	0.75	5	800
JTMA8813/A	TQFN3x3-20	Buck	COT	1	2	20	3	28	0.75	5	800
JTMA8814	TQFN3x3-16	Buck	COT	1	1	20	1.8	28	0.75	5	400
JTMA8815	QFN3.5x3.5-14	Buck	COT	1	1	20	1.8	28	0.75	5	400
JTMA8815	TQFN3x3-16	Buck	COT	1	1	20	1.8	28	0.75	5	400
JTMA8816	TQFN3x3-16	Buck	COT	1	2	20	1.8	28	0.75	5	400
JTMA8819	QFN3x3-20	Buck	COT	1	2	20	3	28	1.8 /1.5 /0.5	5	740
JTMA8819	TQFN3x3-16	Buck	COT	1	2	20	3	28	1.8 /1.5 /0.5	5	740
JTMA8820	TQFN4x4-24	Buck	CM	1	2	15	5	28	0.5	N	3000
JTMA8820	QFN3x3-20	Buck	CM	1	2	15	5	28	0.5	N	3000
JTMA8821	TDFN3x3-10	Buck	COT	1	1	20	1.8	28	0.5	5	250
JTMA8822/C	TQFN3x3-20	Buck	COT	1	2	15	6	25	2	N	550
JTMA8823A/B	TQFN3x3-20	Buck	COT	1	2	15	5.5	25	0.6	N	50
JTMA8868	TQFN3x3-20	Buck	COT	1	2	20	3	28	0.75	5	180
JTMA7088	QFN4x4-24	Multiphase	VM	2	1	60	3.1	13.2	0.85	12	5000
JTMA7165A/B/C	SOP-8P	Buck	VM	1	1	20	2.9	13.2	0.8	12	16000
JTMA7159A	SOP-20	Buck	VM	2	2	30	10	13.2	1	12	5000
JTMA8828	TDFN3x3-10	Buck	COT	1	1	25	1.8	28	0.7	5	250
JTMA8728	TQFN 3x3 16	Buck	COT	1	1	30	1.8	28	0.6	5	600

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